RESUMO
An in vitro perifusion system was used to investigate GnRH release from adult human hypothalami in response to dopamine (DA) and the DA receptor antagonist haloperidol (HAL). Administration of a 1-microM pulse of DA consistently elicited a mean +/- SE 218 +/- 59% increase (P less than 0.05; n = 5) in GnRH release, whereas 1 microM HAL had no effect. Administration of 1 microM DA during three perifusions in which 1 microM HAL was added to the medium failed to alter basal GnRH release. In contrast, DA did evoke an acute 98 +/- 39% increase (P less than 0.06) in GnRH release during three matching perifusions with medium containing the alpha-adrenergic antagonist phentolamine. These studies demonstrate that DA can stimulate in vitro release of GnRH from the adult human hypothalamus by a DA receptor-mediated mechanism.
Assuntos
Dopamina/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Adulto , Idoso , Feminino , Haloperidol/farmacologia , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , PerfusãoRESUMO
Erythrocyte adenosine triphosphate (ATP) was assessed in patients with hepatic disease who had developed hemolytic anemia. Erythrocyte ATP was decreased, and this finding documents another cause for hemolytic anemia in patients with hepatic disease. The decreased erythrocyte ATP is secondary to hypophosphatemia, which is a common biochemical abnormality associated with hepatic disease.