L-tyrosine, a precurosr to melanin, has recently been shown to be a regulator of the melanogenic pathway in some cultured melanoma cell lines. In this paper we demonstrated that L-tyrosine, besides increasing binding capacity for MSH, decreased cooperativity between MSH receptors and increased the level of tyrosinase induction by MSH. Apparently, regulation of MSH receptor activity by L-tyrosin...

levels to normal, although we cannot exclude the possibility that prednisone, administered for immunosuppression, may have contributed to the decrease in plasma p-MSH concentration. The way that the kidney influences r-MSH metabolism is uncertain. Since the patients on haemodialysis who retain their kidneys pass little urine the difference in plasma p-MSH levels between those with kidneys and t...

We examined the effect of temporary renal ischemia (30 min or 60 min) and reperfusion (1 day or 5 days) on the expression of renal aquaporins (AQPs) and urinary concentration in rats with bilateral ischemia-induced acute renal failure (ARF). Next, we tested whether reducing ischemia/reperfusion (I/R) injury by treatment with α-melanocyte stimulating hormone (α-MSH) affects the expression of AQP...

OBJECTIVE In the present paper, we are interested in the effects of gamma-melanocyte-stimulating hormones (gamma-MSHs) on cardiovascular regulatory systems. METHODS Mean arterial pressure (MAP), cerebral blood flow (CBF) and heart rate (HR) were measured in urethane-anaesthetised rats after intravenous administration of lysgamma(2)-MSH, gamma(2)-MSH, gamma(2)-MSH(6-12) or phenylephrine. RES...

Mortality and morbidity in bacterial meningitis remain high in children and adults. Previous studies suggested that inflammatory response to bacterial products apparently continues even after the bactericidal effect of antibiotics, resulting in destruction of the host tissue. Previous studies showed that ACTH410 synthetic uses melanocortin receptors and it was considered that α-MSH shares the f...

The melanocortin-3 (MC3R) and melanocortin-4 (MC4R) receptors are expressed in the brain and are implicated in the regulation of food intake and energy homeostasis. The endogenous agonist ligands for these receptors (α-, β-, γ-MSH and ACTH) are linear peptides with limited receptor subtype selectivity and metabolic stability, thus minimizing their use as probes to characterize the overlapping p...