Neuroendocrine integrative mechanisms in mammalian pineal gland: Effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro
The time course for the decrease in norepinephrine concentration of rat pineal explants in culture indicated a significant fall starting at the 4th hour and completed after 16-24 h of incubation. Significant decreases of serotonin and 5-hydroxyindoleacetic acid (HIAA) levels in tissue, an increase o...
Guardado en:
| Publicado: |
1987
|
|---|---|
| Materias: | |
| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00224731_v27_n1-3_p565_Cardinali http://hdl.handle.net/20.500.12110/paper_00224731_v27_n1-3_p565_Cardinali |
| Aporte de: |
| id |
paper:paper_00224731_v27_n1-3_p565_Cardinali |
|---|---|
| record_format |
dspace |
| spelling |
paper:paper_00224731_v27_n1-3_p565_Cardinali2023-06-08T14:51:02Z Neuroendocrine integrative mechanisms in mammalian pineal gland: Effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro 5 hydroxyindoleacetic acid estradiol follitropin growth hormone luteinizing hormone melatonin noradrenalin phentolamine prolactin propranolol radioisotope serotonin animal cell animal experiment guinea pig methodology nonhuman pineal body rat Animal Comparative Study Guinea Pigs Hydroxyindoleacetic Acid Male Melatonin Norepinephrine Organ Culture Phentolamine Pineal Gland Pituitary Hormones, Anterior Propranolol Rats Receptors, Estradiol Serotonin Sex Hormones Support, Non-U.S. Gov't The time course for the decrease in norepinephrine concentration of rat pineal explants in culture indicated a significant fall starting at the 4th hour and completed after 16-24 h of incubation. Significant decreases of serotonin and 5-hydroxyindoleacetic acid (HIAA) levels in tissue, an increase of HIAA/serotonin ratio, and an increase of melatonin production rate in vitro were also observed as a function of the incubation time. Estradiol (10-7-10-5 M) increased rat pineal melatonin content, testosterone (10-5 M) decreased it and progesterone was devoid of activity when incubated with explants for up to 6 h. The in vitro stimulatory effect of estradiol on rat pineal methoxyindole synthesis was blocked by propranolol but not by phentolamine; propranolol also blocked the increase of nuclear estradiol-receptor complex produced by estrogen exposure of pineal explants. TSH (1-100 ng/ml), growth hormone (10-100 ng/ml) and LH (10 ng/ml) augmented rat pineal melatonin content while 100 ng/ml of FSH decreased it significantly. Prolactin exerted a biphasic effect on rat pineal explants, the lowest concentration augmenting melatonin content while the high concentration depressed it. Deep, intermediate and superficial segments of guinea-pig pineal glands showed an increase in melatonin concentration after a 6-h incubation in the presence of 10-7-10-5 M estradiol. © 1987. 1987 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00224731_v27_n1-3_p565_Cardinali http://hdl.handle.net/20.500.12110/paper_00224731_v27_n1-3_p565_Cardinali |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
5 hydroxyindoleacetic acid estradiol follitropin growth hormone luteinizing hormone melatonin noradrenalin phentolamine prolactin propranolol radioisotope serotonin animal cell animal experiment guinea pig methodology nonhuman pineal body rat Animal Comparative Study Guinea Pigs Hydroxyindoleacetic Acid Male Melatonin Norepinephrine Organ Culture Phentolamine Pineal Gland Pituitary Hormones, Anterior Propranolol Rats Receptors, Estradiol Serotonin Sex Hormones Support, Non-U.S. Gov't |
| spellingShingle |
5 hydroxyindoleacetic acid estradiol follitropin growth hormone luteinizing hormone melatonin noradrenalin phentolamine prolactin propranolol radioisotope serotonin animal cell animal experiment guinea pig methodology nonhuman pineal body rat Animal Comparative Study Guinea Pigs Hydroxyindoleacetic Acid Male Melatonin Norepinephrine Organ Culture Phentolamine Pineal Gland Pituitary Hormones, Anterior Propranolol Rats Receptors, Estradiol Serotonin Sex Hormones Support, Non-U.S. Gov't Neuroendocrine integrative mechanisms in mammalian pineal gland: Effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro |
| topic_facet |
5 hydroxyindoleacetic acid estradiol follitropin growth hormone luteinizing hormone melatonin noradrenalin phentolamine prolactin propranolol radioisotope serotonin animal cell animal experiment guinea pig methodology nonhuman pineal body rat Animal Comparative Study Guinea Pigs Hydroxyindoleacetic Acid Male Melatonin Norepinephrine Organ Culture Phentolamine Pineal Gland Pituitary Hormones, Anterior Propranolol Rats Receptors, Estradiol Serotonin Sex Hormones Support, Non-U.S. Gov't |
| description |
The time course for the decrease in norepinephrine concentration of rat pineal explants in culture indicated a significant fall starting at the 4th hour and completed after 16-24 h of incubation. Significant decreases of serotonin and 5-hydroxyindoleacetic acid (HIAA) levels in tissue, an increase of HIAA/serotonin ratio, and an increase of melatonin production rate in vitro were also observed as a function of the incubation time. Estradiol (10-7-10-5 M) increased rat pineal melatonin content, testosterone (10-5 M) decreased it and progesterone was devoid of activity when incubated with explants for up to 6 h. The in vitro stimulatory effect of estradiol on rat pineal methoxyindole synthesis was blocked by propranolol but not by phentolamine; propranolol also blocked the increase of nuclear estradiol-receptor complex produced by estrogen exposure of pineal explants. TSH (1-100 ng/ml), growth hormone (10-100 ng/ml) and LH (10 ng/ml) augmented rat pineal melatonin content while 100 ng/ml of FSH decreased it significantly. Prolactin exerted a biphasic effect on rat pineal explants, the lowest concentration augmenting melatonin content while the high concentration depressed it. Deep, intermediate and superficial segments of guinea-pig pineal glands showed an increase in melatonin concentration after a 6-h incubation in the presence of 10-7-10-5 M estradiol. © 1987. |
| title |
Neuroendocrine integrative mechanisms in mammalian pineal gland: Effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro |
| title_short |
Neuroendocrine integrative mechanisms in mammalian pineal gland: Effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro |
| title_full |
Neuroendocrine integrative mechanisms in mammalian pineal gland: Effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro |
| title_fullStr |
Neuroendocrine integrative mechanisms in mammalian pineal gland: Effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro |
| title_full_unstemmed |
Neuroendocrine integrative mechanisms in mammalian pineal gland: Effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro |
| title_sort |
neuroendocrine integrative mechanisms in mammalian pineal gland: effects of steroid and adenohypophysial hormones on melatonin synthesis in vitro |
| publishDate |
1987 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00224731_v27_n1-3_p565_Cardinali http://hdl.handle.net/20.500.12110/paper_00224731_v27_n1-3_p565_Cardinali |
| _version_ |
1768544443536769024 |