Expression of orexin-A and orexin receptors in the kidney and the presence of orexin-A-like immunoreactivity in human urine.

Orexin-A (hypocretin-1), a neuropeptide with stimulatory actions on arousal and appetite, was originally shown to be specifically expressed in the hypothalamus. We studied expression of orexin-A and orexin receptors in the kidney and the presence of orexin-A-like immunoreactivity in human urine. Immunocytochemistry showed that orexin-A-like immunoreactivity and two types of orexin receptors (types 1 and 2) were localized in the tubules of the human kidney obtained at autopsy.

Effects of adipokines on expression of adrenomedullin and endothelin-1 in cultured vascular endothelial cells.

Obesity is a major risk factor for the development of hypertension. Adipokines may cause hypertension by acting both centrally and directly on the vascular vessels. We wished to clarify whether three adipokines, leptin, resistin and tumor necrosis factor-alpha, affect expression of adrenomedullin and endothelin-1 in vascular endothelial cells.

Elevated plasma levels of immunoreactive urotensin II and its increased urinary excretion in patients with Type 2 diabetes mellitus: association with progress of diabetic nephropathy.

Urotensin II (UII) is the most potent vasoconstrictor peptide ever identified. In order to clarify the pathophysiological role of UII in diabetes mellitus, we examined plasma immunoreactive UII levels and urinary excretion of immunoreactive UII in 10 control subjects and 48 patients with Type 2 diabetes mellitus. The patients were divided into three groups according to the renal function: Group I with Ccr > or = 70 ml/min, group II with 30 < or = Ccr <70 ml/min and group III with Ccr <30 ml/min.

Increased plasma urotensin II levels in patients with diabetes mellitus.

Urotensin II (UII) is the most potent vasoconstrictor peptide, whereas it acts as a vasodilator on some arteries. We studied plasma levels of UII in diabetic patients with normal serum creatinine levels (<90 micromol/l) and the expression of UII and its receptor in cultured human vascular endothelial cells. Plasma UII levels were significantly elevated by 1.

Three vasoactive peptides, endothelin-1, adrenomedullin and urotensin-II, in human tumour cell lines of different origin: expression and effects on proliferation.

Evidence has accumulated showing that vasoactive peptides, such as endothelin-1, adrenomedullin and urotensin-II, are expressed in various kinds of tumour cells. In the present study, the expression of endothelin-1 and endothelin receptors was studied in eight human tumour cell lines: T98G (glioblastoma), IMR-32 and NB69 (neuroblastoma), BeWo (choriocarcinoma), SW-13 (adrenocortical carcinoma), DLD-1 (colonic carcinoma), HeLa (cervical carcinoma) and VMRC-RCW (renal carcinoma). Reverse transcriptase-PCR showed expression of endothelin-1 mRNA in seven out of the eight cell lines, the exception being BeWo cells.

Expression of prolactin-releasing peptide and its receptor in the human adrenal glands and tumor tissues of adrenocortical tumors, pheochromocytomas and neuroblastomas.

Adrenal tumors, such as pheochromocytomas, are known to express various peptides and their receptors. Prolactin-releasing peptide (PrRP) is a novel neuropeptide isolated from bovine hypothalamic tissues. In the present study, expression of PrRP receptor was studied in the human brain, pituitaries, adrenal glands and tumor tissues of adrenocortical tumors, pheochromocytomas, a ganglioneuroblastoma and neuroblastomas by reverse transcriptase polymerase chain reaction (RT-PCR) and Northern blot analysis.