Insulin-like growth factor I is essential for terminal end bud formation and ductal morphogenesis during mammary development.

Ruan W, Kleinberg DL

Endocrinology1 Nov 1999Cited by 173 (Europe PMC)

PMID10537134DOI10.1210/endo.140.11.7095PepBankPUB-10537134

Publisher page PubMedAsk about this study

Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study10

2 results from studies that gave the peptide. No result from this study comes from people.

01AnimalAnimal study (in vivo)Efficacy outcome
In IGF-I-null animals, des IGF-I alone increased terminal end bud numbers versus controls.
In plain wordsIn IGF-I-null animals, des IGF-I alone increased terminal end buds versus controls.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseTerminal end bud formation
Study
n: not reported in source
IGF-I(-/-) null female animals
Comparator
Controls
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Studied dose
Dose not stated · 5 daysAs given in this study.
Measurements
Terminal end buds
1.3 count
controls
Terminal end buds
20.5 count
without added E2
Source sentences
Summary
The number of TEBs rose from a mean of 1.3 in controls to 20.5 without added E2 (P < 0.009), and from 1.7 to 21 when des (1-3) IGF-I was given together with E2 (P < 0.006).
1 context sentence(design, population, supporting numbers)
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
Report a problemFND-1053713401
02AnimalAnimal study (in vivo)Efficacy outcome
In IGF-I-null animals, des(1‑3)IGF-I alone increased duct numbers from 15 to 24.5.
In plain wordsIn IGF-I-null animals, des(1‑3)IGF-I alone increased duct numbers from 15 to 24.5.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseDuct number
Study
n: not reported in source
IGF-I(-/-) null female animals
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Studied dose
Dose not stated · 5 daysAs given in this study.
Measurements
Ducts
15 count
reference
Ducts
24.5 count
IGF-I alone
Source sentences
Summary
The number of ducts increased significantly from a mean of 12 to 27 in response to IGF-I and E2, and from 15 to 24.5 with IGF-I alone.
1 context sentence(design, population, supporting numbers)
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
Report a problemFND-1053713403

Studies that did not test the peptide alone8

In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking IGF-1 DES (des(1-3)IGF-I).

03AnimalNot a test of IGF-1 DES (des(1-3)IGF-I) aloneAnimal study (in vivo)Efficacy outcome
In IGF-I-null animals, des IGF-I with E2 increased terminal end bud numbers versus controls.
In plain wordsIn IGF-I-null animals, des IGF-I with E2 increased terminal end buds versus controls.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseTerminal end bud formation with estradiol
Study
n: not reported in source
IGF-I(-/-) null female animals
Comparator
Controls
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Measurements
Terminal end buds
1.7 count
controls
Terminal end buds
21 count
des IGF-I with E2
Source sentences
Summary
The number of TEBs rose from a mean of 1.3 in controls to 20.5 without added E2 (P < 0.009), and from 1.7 to 21 when des (1-3) IGF-I was given together with E2 (P < 0.006).
1 context sentence(design, population, supporting numbers)
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking IGF-1 DES (des(1-3)IGF-I).
Report a problemFND-1053713402
04AnimalNot a test of IGF-1 DES (des(1-3)IGF-I) aloneAnimal study (in vivo)Efficacy outcome
In IGF-I-null animals, des(1‑3)IGF-I with E2 increased duct numbers from 12 to 27.
In plain wordsIn IGF-I-null animals, des(1‑3)IGF-I with E2 increased duct numbers from 12 to 27.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseDuct number with estradiol
Study
n: not reported in source
IGF-I(-/-) null female animals
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Measurements
Ducts
12 count
reference
Ducts
27 count
IGF-I with E2
Source sentences
Summary
The number of ducts increased significantly from a mean of 12 to 27 in response to IGF-I and E2, and from 15 to 24.5 with IGF-I alone.
1 context sentence(design, population, supporting numbers)
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking IGF-1 DES (des(1-3)IGF-I).
Report a problemFND-1053713404
05AnimalNot a test of IGF-1 DES (des(1-3)IGF-I) aloneAnimal study (in vivo)Efficacy outcome
In knockout animals, des IGF-I with E2 increased terminal end buds between 5 and 14 days.
In plain wordsIn knockout animals, des IGF-I with E2 increased terminal end buds between 5 and 14 days.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseTerminal end buds over treatment time
Study
n: not reported in source
IGF-I(-/-) null female animals
Comparator
5 days of combination treatment
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Measurements
Terminal end buds
21 count
5 days
Terminal end buds
41 count
14 days
Source sentences
Summary
We found that there was a significant increase from 5 to 14 days in the number of TEBs (mean: 21 vs. 41) and the area of the mammary fat pad occupied by glands (mean: 10 vs. 20%).
2 context sentences(design, population, supporting numbers)
Summary · context
To determine whether IGF-I was also responsible for further ductal morphogenesis, we administered des (1-3) IGF-I + E2 to the knockout animals for 14 days and compared the effects of this combination of hormones on mammary development with those observed after 5 days.
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking IGF-1 DES (des(1-3)IGF-I).
Report a problemFND-1053713405
06AnimalNot a test of IGF-1 DES (des(1-3)IGF-I) aloneAnimal study (in vivo)Efficacy outcome
In knockout animals, des IGF-I with E2 increased gland-occupied mammary fat pad area between 5 and 14 days.
In plain wordsIn knockout animals, des IGF-I with E2 increased gland-occupied fat pad area between 5 and 14 days.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseMammary fat pad area occupied by glands
Study
n: not reported in source
IGF-I(-/-) null female animals
Comparator
5 days of combination treatment
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Measurements
Gland-occupied area
10%
5 days
Gland-occupied area
20%
14 days
Source sentences
Summary
We found that there was a significant increase from 5 to 14 days in the number of TEBs (mean: 21 vs. 41) and the area of the mammary fat pad occupied by glands (mean: 10 vs. 20%).
2 context sentences(design, population, supporting numbers)
Summary · context
To determine whether IGF-I was also responsible for further ductal morphogenesis, we administered des (1-3) IGF-I + E2 to the knockout animals for 14 days and compared the effects of this combination of hormones on mammary development with those observed after 5 days.
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking IGF-1 DES (des(1-3)IGF-I).
Report a problemFND-1053713406
07AnimalNot a test of IGF-1 DES (des(1-3)IGF-I) aloneAnimal study (in vivo)Efficacy outcome
In knockout animals receiving des IGF-I with E2, ducts elongated during extended treatment.
In plain wordsIn knockout animals receiving des IGF-I with E2, ducts elongated during extended treatment.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseDuct elongation
Study
n: not reported in source
IGF-I(-/-) null female animals
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Source sentences
Summary
There was elongation and thickening of the ducts which accounted for the increased area that was occupied by ductal structures.
2 context sentences(design, population, supporting numbers)
Summary · context
To determine whether IGF-I was also responsible for further ductal morphogenesis, we administered des (1-3) IGF-I + E2 to the knockout animals for 14 days and compared the effects of this combination of hormones on mammary development with those observed after 5 days.
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking IGF-1 DES (des(1-3)IGF-I).
Report a problemFND-1053713407
08AnimalNot a test of IGF-1 DES (des(1-3)IGF-I) aloneAnimal study (in vivo)Efficacy outcome
In knockout animals receiving des IGF-I with E2, ducts thickened during extended treatment.
In plain wordsIn knockout animals receiving des IGF-I with E2, ducts thickened during extended treatment.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseDuct thickening
Study
n: not reported in source
IGF-I(-/-) null female animals
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Source sentences
Summary
There was elongation and thickening of the ducts which accounted for the increased area that was occupied by ductal structures.
2 context sentences(design, population, supporting numbers)
Summary · context
To determine whether IGF-I was also responsible for further ductal morphogenesis, we administered des (1-3) IGF-I + E2 to the knockout animals for 14 days and compared the effects of this combination of hormones on mammary development with those observed after 5 days.
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking IGF-1 DES (des(1-3)IGF-I).
Report a problemFND-1053713408
09AnimalNot a test of IGF-1 DES (des(1-3)IGF-I) aloneAnimal study (in vivo)Efficacy outcome
In knockout animals receiving des IGF-I with E2, duct numbers did not significantly increase from 5 to 14 days.
In plain wordsIn knockout animals receiving des IGF-I with E2, duct numbers did not significantly increase from 5 to 14 days.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
No significant changeDuct number over treatment time
Study
n: not reported in source
IGF-I(-/-) null female animals
Comparator
5 days of combination treatment
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Source sentences
Summary
There was no significant increase in the number of ducts.
2 context sentences(design, population, supporting numbers)
Summary · context
To determine whether IGF-I was also responsible for further ductal morphogenesis, we administered des (1-3) IGF-I + E2 to the knockout animals for 14 days and compared the effects of this combination of hormones on mammary development with those observed after 5 days.
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking IGF-1 DES (des(1-3)IGF-I).
Report a problemFND-1053713409
10AnimalNot a test of IGF-1 DES (des(1-3)IGF-I) aloneAnimal study (in vivo)Efficacy outcome
In knockout animals receiving des IGF-I with E2, numerous buds appeared along ductal structures.
In plain wordsIn knockout animals receiving des IGF-I with E2, numerous buds appeared along ducts.
Peptide
IGF-1 DES (des(1-3)IGF-I)
Outcome
IncreaseDuctal buds
Study
n: not reported in source
IGF-I(-/-) null female animals
Outcome group
Sex hormones and fertility · Reproductive and sexual health
Source sentences
Summary
However, there was the appearance of a large number of buds along the length of the ductal structures, suggesting the beginning of side branching.
2 context sentences(design, population, supporting numbers)
Summary · context
To determine whether IGF-I was also responsible for further ductal morphogenesis, we administered des (1-3) IGF-I + E2 to the knockout animals for 14 days and compared the effects of this combination of hormones on mammary development with those observed after 5 days.
Summary · context
That the deficiency in mammary gland development was related to the absence of IGF-I was underscored by the observation that des (1-3) IGF-I administration to IGF-I(-/-) null animals for 5 days caused significant mammary gland development as measured by TEB formation and branching of ducts.
In this study, IGF-1 DES (des(1-3)IGF-I) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking IGF-1 DES (des(1-3)IGF-I).
Report a problemFND-1053713410

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 3Current
21 Oct 2026, 15:58 UTC
Study results updated
Version 2
21 Oct 2026, 13:52 UTC
Study data updated · source update from Europe PMC
Version 1
21 Oct 2026, 12:50 UTC
First added · source update from Europe PMC

Insulin-like growth factor I is essential for terminal end bud formation and ductal morphogenesis during mammary development.

Summary

Results from this study10

Studies that did not test the peptide alone8

Version history

Subjects

Publication types

MeSH terms