Secretion of free and conjugated steroids by the horse testis into lymph and venous blood.
Abstract: In 3 testes of 2 adult Pony stallions under halothane anaesthesia, catheters were inserted into a vein and a lymphatic vessel in the spermatic cord and into a vein on the surface of the testis. Lymph and venous blood were collected from the catheters in the cord and p-aminohippurate (2% w/v, 0 . 1 ml/min) was infused into the vein on the testis to determine blood flow by dilution. After 1 h, 6000 i.u. hCG was injected i.v. and collections continued for 45 min. The testes weighed 126-176 g. Lymph flow was 20-150 microliter/min before hCG and 100-270 microliter/min after hCG; the range of blood flow, with a haematocrit of about 22%, was unchanged (27-47 ml/min) after hCG. The concentration of testosterone in spermatic venous blood rose from 6-20 ng/ml to 160-270 ng/ml within about 30 min after hCG. Peripheral levels rose from about 2 to 6 ng/ml and lymph levels increased from 9-20 to 34-150 ng/ml after hCG. In contrast, the concentrations of oestrone sulphate in spermatic venous blood were about 400 ng/ml, compared with about 250 ng/ml in peripheral blood, while lymph values ranged from 600 to 1500 ng/ml; hCG had no consistent effect. DHA and its sulphate were present in spermatic venous blood at concentrations (about 3 and 5 ng/ml respectively) slightly higher than in peripheral blood (1 . 7 and 2 . 5 ng/ml), but the sulphate was at a very much higher concentration in lymph (about 5 and 200 ng/ml respectively). These results indicate that testicular lymph is an important route for the secretion of conjugated steroids by the horse testis.
Publication Date: 1982-01-01 PubMed ID: 6300388
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- Journal Article
Summary
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This study investigates how horse testes secrete free and conjugated steroids into lymph and venous blood. Using adult Pony stallions, the study finds that testicular lymph is a key pathway for the secretion of these steroids.
Research Methods
- The researchers used three testes from two adult Pony stallions for this experiment.
- Under halothane anesthesia, catheters were inserted into a vein and a lymphatic vessel in the spermatic cord, as well as into a vein on the surface of the testis.
- The researchers collected lymph and venous blood from the catheters in the cord and then infused p-aminohippurate (2% w/v, 0 . 1 ml/min) into the vein on the testis. This was done to determine blood flow through dilution.
- Afterward, they injected 6000 i.u. hCG intravenously and continued collections for 45 minutes.
- The weight of the testes used in the experiment ranged from 126-176 grams.
Results: Lymph and Blood Flow
- Before the injection of hCG, lymph flow was between 20-150 microliters/minute and increased to 100-270 microliters/minute after the injection.
- The blood flow remained unchanged after the hCG injection (27-47 ml/minute).
Results: Steroid Concentrations
- The concentration of testosterone in spermatic venous blood increased drastically after the hCG injection, rising from 6-20 ng/ml to 160-270 ng/ml within approximately 30 minutes.
- Similarly, peripheral levels rose from about 2 to 6 ng/ml after hCG, while lymph levels increased from 9-20 to 34-150 ng/ml.
- In contrast, the concentrations of oestrone sulphate in spermatic venous blood were about 400 ng/ml, and about 250 ng/ml in peripheral blood, while lymph values ranged from 600 to 1500 ng/ml. There was no consistent effect of hCG injection on oestrone sulphate levels.
- DHA and its sulphate were present in spermatic venous blood at concentrations slightly higher than in peripheral blood, but the sulphate was at a very much higher concentration in lymph (about 5 and 200 ng/ml respectively).
Conclusion
- Based on these results, the researchers concluded that testicular lymph is an essential pathway for the secretion of conjugated steroids by the horse testis.
Cite This Article
APA
Setchell BP, Cox JE.
(1982).
Secretion of free and conjugated steroids by the horse testis into lymph and venous blood.
J Reprod Fertil Suppl, 32, 123-127.
Publication
Researcher Affiliations
MeSH Terms
- Animals
- Dehydroepiandrosterone / analogs & derivatives
- Dehydroepiandrosterone / metabolism
- Dehydroepiandrosterone Sulfate
- Estrogens, Conjugated (USP) / metabolism
- Estrone / analogs & derivatives
- Estrone / metabolism
- Gonadal Steroid Hormones / blood
- Horses
- Lymph / physiology
- Male
- Regional Blood Flow
- Testis / blood supply
- Testis / metabolism
- Testosterone / metabolism
Citations
This article has been cited 6 times.- Hess RA, Sharpe RM, Hinton BT. Estrogens and development of the rete testis, efferent ductules, epididymis and vas deferens.. Differentiation 2021 Mar-Apr;118:41-71.
- Navaneethabalakrishnan S, Goodlett BL, Lopez AH, Rutkowski JM, Mitchell BM. Hypertension and reproductive dysfunction: a possible role of inflammation and inflammation-associated lymphangiogenesis in gonads.. Clin Sci (Lond) 2020 Dec 23;134(24):3237-3257.
- Breslin JW, Yang Y, Scallan JP, Sweat RS, Adderley SP, Murfee WL. Lymphatic Vessel Network Structure and Physiology.. Compr Physiol 2018 Dec 13;9(1):207-299.
- Hess RA, Cooke PS. Estrogen in the male: a historical perspective.. Biol Reprod 2018 Jul 1;99(1):27-44.
- Cooke PS, Nanjappa MK, Ko C, Prins GS, Hess RA. Estrogens in Male Physiology.. Physiol Rev 2017 Jul 1;97(3):995-1043.
- Hess RA. Estrogen in the adult male reproductive tract: a review.. Reprod Biol Endocrinol 2003 Jul 9;1:52.
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