Prolactin Secretion Response Research Articles

Differential behavioural and hormonal responses to two different stressors (footshocking and immobilization) in sheep.

Two different stressors footshocking and immobilization applied for 3 days induced in sheep differential behavioural and hormonal responses in cortisol and prolactin secretion. Immobilization drastically disturbed rumen motoric activity (significantly attenuated its contractions), caused loss of appetite and severe general depression. Footshocking did not induce any of these symptoms. Immobilization induced 2-3 fold higher rise of plasma cortisol mesors on the days of stressing as compared to footshocking. On the poststressing days after footshocking as well as after immobilization plasma cortisol mesors fell to 50% of the prestimulatory values. The rise of plasma prolactin mesors in footshocked and in immobilized animals on the days of stressing was nearly of the same magnitude. However, a significant difference in the response of prolactin secretion between footshocked and immobilized animals occurred in the circadian rhythmicity of the hormone secretion. Footshocking induced circadian rhythmicity with characteristic acrophases, while immobilization did not induce the circadian pattern of prolactin secretion. An attempt of interpretation of the described phenomena has been undertaken.

Prolactin secretion in kidney transplant patients

In 27 male patients with a functioning kidney transplant and in 12 healthy male subjects plasma prolactin levels were estimated under baseline, inhibitory and stimulatory conditions, respectively. Kidney transplant patients (KTP) showed normal baseline plasma levels of prolactin, and a normal response of prolactinaemia to alpha-bromocriptine. In contrast, administration of chlorpromazine was followed by an exaggerated response of prolactin secretion in KTP as compared with normals. Type of immunosuppressive therapy (cyclosporine A or azathioprine) did not influence significantly the plasma prolactin profile in KTP under either inhibitory or stimulatory conditions.

Prolactin secretion response to TRH stimulation in acute and chronic schizophrenic patients under neuroleptic treatment.

Prolactin (PRL) serum levels in a group of patients with acute schizophrenia (AS) and in a group of patients with chronic schizophrenia (CS) have been investigated in order to differentiate the dopaminergic sensitivity in response to chlorpromazine (CPZ) treatment. AS patients show both a greater dopaminergic sensitivity to CPZ and a stronger response in PRL secretion to TRH stimulation after a 14-day CPZ treatment.