Serotonin in golden hamster testes: Testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition
Serotonin (5-HT) is found in the gonads and accessory reproductive organs of several species. The golden (Syrian) hamster is a seasonal breeder. Exposure of male adult hamsters to short days for 14 weeks results in a severe gonadal regression, while after a photoinhibition period of 22 weeks a spont...
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1999
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00283835_v69_n4_p299_Frungieri http://hdl.handle.net/20.500.12110/paper_00283835_v69_n4_p299_Frungieri |
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paper:paper_00283835_v69_n4_p299_Frungieri2023-06-08T14:55:03Z Serotonin in golden hamster testes: Testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition Gonadotropins Hamster Immunohistochemistry Photoperiod Serotonin Steroidogenesis Testis 5 hydroxyindoleacetic acid chorionic gonadotropin neurotransmitter serotonin testosterone age animal experiment animal tissue article immunoreactivity Leydig cell light dark cycle male mast cell nonhuman parenchyma photoperiodicity physiology priority journal sexual development sexual maturation steroidogenesis Syrian hamster testis development testosterone synthesis Serotonin (5-HT) is found in the gonads and accessory reproductive organs of several species. The golden (Syrian) hamster is a seasonal breeder. Exposure of male adult hamsters to short days for 14 weeks results in a severe gonadal regression, while after a photoinhibition period of 22 weeks a spontaneous testicular recrudescence occurs. The aim of this study was to investigate the presence of 5-HT and its major metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the gonads of golden hamsters, its immunolocation and its physiological role in the testis. The influence of age and photoperiod was also analyzed. Hamsters of 23, 36, 46, 60 and 90 days of age were kept in long photoperiod (LP: 14:10 h light/dark), and adult animals were exposed either to LP or to short photoperiod (SP: 6:18 h light/dark) for 14 and 22 weeks. Testicular parenchyma and capsule levels of 5-HT and 5-HIAA increased significantly at ages of 36 and 60-90 days, but decreased markedly during the exposure of adult hamsters to SP for 14 and 22 weeks. Mast cells were found exclusively in the testicular capsule. The testicular number of mast cells increased concomitantly with age, but decreased in adult hamsters exposed to SP. Mast and Leydig cells presented 5-HT-positive immunoreactivity. During sexual maturation as well as during the transfer of adult hamsters from LP to SP, the 5-HIAA/5-HT ratio showed the highest values in active adult animals, indicating that the increase in testicular 5-HT levels in adulthood is accompanied by an augment in 5-HT turnover. In vitro basal and hCG-stimulated testosterone production was significantly inhibited in presence of physiological concentrations of 5-HT. In conclusion, the present studies demonstrate the existence of 5-HT in mast cells and Leydig cells of hamster testes, as well as describe an inhibitory action of this neurotransmitter on gonadal testosterone production. Furthermore, the age-dependent and photoperiodic-related changes detected in testicular 5-HT levels suggest that this neurotransmitter might act as an important local modulator of the action of gonadotropins on steroidogenesis during sexual development and during the photoperiodic regression-recrudescence transition in the golden hamster. 1999 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00283835_v69_n4_p299_Frungieri http://hdl.handle.net/20.500.12110/paper_00283835_v69_n4_p299_Frungieri |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Gonadotropins Hamster Immunohistochemistry Photoperiod Serotonin Steroidogenesis Testis 5 hydroxyindoleacetic acid chorionic gonadotropin neurotransmitter serotonin testosterone age animal experiment animal tissue article immunoreactivity Leydig cell light dark cycle male mast cell nonhuman parenchyma photoperiodicity physiology priority journal sexual development sexual maturation steroidogenesis Syrian hamster testis development testosterone synthesis |
| spellingShingle |
Gonadotropins Hamster Immunohistochemistry Photoperiod Serotonin Steroidogenesis Testis 5 hydroxyindoleacetic acid chorionic gonadotropin neurotransmitter serotonin testosterone age animal experiment animal tissue article immunoreactivity Leydig cell light dark cycle male mast cell nonhuman parenchyma photoperiodicity physiology priority journal sexual development sexual maturation steroidogenesis Syrian hamster testis development testosterone synthesis Serotonin in golden hamster testes: Testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition |
| topic_facet |
Gonadotropins Hamster Immunohistochemistry Photoperiod Serotonin Steroidogenesis Testis 5 hydroxyindoleacetic acid chorionic gonadotropin neurotransmitter serotonin testosterone age animal experiment animal tissue article immunoreactivity Leydig cell light dark cycle male mast cell nonhuman parenchyma photoperiodicity physiology priority journal sexual development sexual maturation steroidogenesis Syrian hamster testis development testosterone synthesis |
| description |
Serotonin (5-HT) is found in the gonads and accessory reproductive organs of several species. The golden (Syrian) hamster is a seasonal breeder. Exposure of male adult hamsters to short days for 14 weeks results in a severe gonadal regression, while after a photoinhibition period of 22 weeks a spontaneous testicular recrudescence occurs. The aim of this study was to investigate the presence of 5-HT and its major metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the gonads of golden hamsters, its immunolocation and its physiological role in the testis. The influence of age and photoperiod was also analyzed. Hamsters of 23, 36, 46, 60 and 90 days of age were kept in long photoperiod (LP: 14:10 h light/dark), and adult animals were exposed either to LP or to short photoperiod (SP: 6:18 h light/dark) for 14 and 22 weeks. Testicular parenchyma and capsule levels of 5-HT and 5-HIAA increased significantly at ages of 36 and 60-90 days, but decreased markedly during the exposure of adult hamsters to SP for 14 and 22 weeks. Mast cells were found exclusively in the testicular capsule. The testicular number of mast cells increased concomitantly with age, but decreased in adult hamsters exposed to SP. Mast and Leydig cells presented 5-HT-positive immunoreactivity. During sexual maturation as well as during the transfer of adult hamsters from LP to SP, the 5-HIAA/5-HT ratio showed the highest values in active adult animals, indicating that the increase in testicular 5-HT levels in adulthood is accompanied by an augment in 5-HT turnover. In vitro basal and hCG-stimulated testosterone production was significantly inhibited in presence of physiological concentrations of 5-HT. In conclusion, the present studies demonstrate the existence of 5-HT in mast cells and Leydig cells of hamster testes, as well as describe an inhibitory action of this neurotransmitter on gonadal testosterone production. Furthermore, the age-dependent and photoperiodic-related changes detected in testicular 5-HT levels suggest that this neurotransmitter might act as an important local modulator of the action of gonadotropins on steroidogenesis during sexual development and during the photoperiodic regression-recrudescence transition in the golden hamster. |
| title |
Serotonin in golden hamster testes: Testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition |
| title_short |
Serotonin in golden hamster testes: Testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition |
| title_full |
Serotonin in golden hamster testes: Testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition |
| title_fullStr |
Serotonin in golden hamster testes: Testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition |
| title_full_unstemmed |
Serotonin in golden hamster testes: Testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition |
| title_sort |
serotonin in golden hamster testes: testicular levels, immunolocalization and role during sexual development and photoperiodic regression-recrudescence transition |
| publishDate |
1999 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00283835_v69_n4_p299_Frungieri http://hdl.handle.net/20.500.12110/paper_00283835_v69_n4_p299_Frungieri |
| _version_ |
1768542070155247616 |