Somatostatin treatment affects testicular function in stallions.
Abstract: This study investigated the regulation of growth hormone (GH) release in stallions and tested the hypothesis that the somatotrophic axis influences testicular function. Basal plasma GH concentrations, effects of an experimental decrease of GH release on testicular function and an opioidergic regulation of GH release were investigated in Shetland stallions (n=6). No seasonal variations in plasma GH concentrations were found over a 12-month period. Treatment with the somatostatin analogue octreotid (100mg twice daily over 10 days) caused a decrease in semen motility from 38.7+/-8.4% progressively motile spermatozoa before treatment to 18.3+/-5.4% on day 3 after end of treatment (P<0.05). Values returned to 35.0+/-8.5% on day 5 after treatment. On the last day of octreotid treatment, a hCG stimulation test was performed (3000IU hCG i.v.). The hCG-induced testosterone release was significantly higher in saline treated than in octreotid pretreated animals (P<0.05). Neither plasma GH concentrations nor volume and density of ejaculates, total sperm count, or semen morphology were different between saline and octreotid treatments. Injection of the opioid antagonist naloxone (0.5mg/kg) significantly increased GH release in June (from 1.1+/-0.3ng/ml before to 3.7+/-2.2), while a minor and not significant increase occurred in January. In conclusion, our results indicate a non-seasonal basal GH release with a fine-modulation by season-dependent opioidergic mechanisms in the male horse. A transient decrease in semen motility and hCG-induced testosterone release following ocreotid treatment indicate a role of GH in the regulation of testicular function in stallions.
Publication Date: 2003-03-07 PubMed ID: 12620589DOI: 10.1016/s0093-691x(02)01361-4Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research explores the effects of somatostatin treatment on the functioning of the testes in stallions, finding deductions in the sperm motility and hormonal production which recovered after treatment ceased.
Overview of Research
- This study aimed to understand the role of the growth hormone (GH) in the male horse, particularly in terms of its impact on testicular function. It also looked at whether the levels and release of GH were influenced by the different times of the year. A total of six Shetland stallions were observed for this purpose.
Methodology
- The researchers monitored the base level GH concentrations in the stallion’s blood over a year and found no seasonal variations.
- Next, they carried out a treatment involving octreotid, a somatostatin analogue. Doses of 100mg were given twice a day for 10 days.
- The octreotide was used to artificially lower GH release and observe its impact on testicular function. Following this treatment, there was a notable decrease in semen motility (the percentage of sperm moving in a progressive manner) from around 38.7% to 18.3% on the third day after treatment ended.
- However, the semen motility rate recovered to around 35% by the fifth day after the treatment.
- The functions of the testes were further examined using a hormonal stimulation test with Human Chorionic Gonadotropin (hCG). It was observed that the testosterone release induced by hCG application was significantly higher in animals that had been pretreated with saline rather than octreotid.
- The effects of opioid regulation on GH release were also investigated using the opioid antagonist naloxone. GH release levels rose significantly in the month of June after naloxone administration but the increase was nominal and non-significant in January.
Conclusions
- In summary, the study indicates that GH release in the male horse is non-seasonal, however its modulation is subtly affected by season-dependent opioid mechanisms.
- The noticeable drop in semen motility and testosterone production post-octreotid treatment suggests that GH has a role in the regulation of testicular function in stallions. However, these effects were found to be transient and levels normalized once the treatment was halted.
Cite This Article
APA
Aurich JE, Kranski S, Parvizi N, Aurich C.
(2003).
Somatostatin treatment affects testicular function in stallions.
Theriogenology, 60(1), 163-174.
https://doi.org/10.1016/s0093-691x(02)01361-4 Publication
Researcher Affiliations
- Clinic for Obstetrics, Gynecology and Andrology, University of Veterinary Sciences, Vienna, Austria.
MeSH Terms
- Animals
- Growth Hormone / blood
- Growth Hormone / metabolism
- Hormones / pharmacology
- Horses / blood
- Horses / physiology
- Male
- Naloxone / pharmacology
- Narcotic Antagonists / pharmacology
- Octreotide / pharmacology
- Opioid Peptides / antagonists & inhibitors
- Opioid Peptides / physiology
- Seasons
- Secretory Rate / drug effects
- Somatostatin / pharmacology
- Sperm Motility / drug effects
- Testis / drug effects
- Testis / physiology
Citations
This article has been cited 3 times.- Salvio G, Martino M, Balercia G, Arnaldi G. Acromegaly and male sexual health.. Rev Endocr Metab Disord 2022 Jun;23(3):671-678.
- Yilmaz MK, Sulu C, Ozkaya HM, Kadioglu A, Ortac M, Kadioglu P. Evaluation of sex hormone profile and semen parameters in acromegalic male patients.. J Endocrinol Invest 2021 Dec;44(12):2799-2808.
- Frank N, Hermida P, Sanchez-Londoño A, Singh R, Gradil CM, Uricchio CK. Blood Glucose and Insulin Concentrations after Octreotide Administration in Horses With Insulin Dysregulation.. J Vet Intern Med 2017 Jul;31(4):1188-1192.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
