vasoactive-intestinal-peptide and Acidosis

Pheochromocytoma (PHEO) clinical manifestations generally mirror excessive catecholamines secretion; rarely the clinical picture may reflect secretion of other hormones. Watery diarrhea, hypokalemia and achlorhydria (WDHA) is a rare syndrome related to excessive secretion of vasoactive intestinal peptide (VIP).. A 73-year-old hypotensive man affected by adrenal PHEO presented with weight loss and watery diarrhea associated with hypokalemia, hyperchloremic metabolic acidosis (anion gap 15 mmol/l) and a negative urinary anion gap. Abdominal computed tomography scan showed a right adrenal PHEO, 8.1 cm in maximum diameter, with tracer uptake on. A rare case of WDHA syndrome caused by malignant VIP-secreting PHEO was diagnosed. High levels of circulating VIP were responsible of the rapidly evolving clinical picture with massive dehydration and weight loss along with severe hyperchloremic metabolic acidosis and hypokalemia due to the profuse untreatable diarrhea. The rescue treatment with lanreotide was unsuccessful because of the paucity of somatostatin-receptor-2A on VIP-secreting PHEO chromaffin cells.

Topics: Acidosis; Adrenal Gland Neoplasms; Adrenalectomy; Aged; Chromaffin Cells; Diarrhea; Humans; Hypokalemia; Male; Peptides, Cyclic; Peripheral Nervous System Neoplasms; Pheochromocytoma; Radionuclide Imaging; Receptors, Somatostatin; Somatostatin; Syndrome; Tomography, X-Ray Computed; Vasoactive Intestinal Peptide; Weight Loss

The turtle urinary bladder possesses an active transport mechanism for the electrogenic secretion of alkali. This process is independent of exogenous Cl and Na, induced by cyclic AMP (cAMP), and potentiated in bladders from NaHCO3-loaded (alkalotic) turtles. In the present study, it is shown that the serosal addition of vasoactive intestinal peptide (VIP) induces rapidly developing parallel increases in alkali secretion and in the short-circuiting current carried by this secretion. The VIP-induced increment in alkali secretion is greater in the presence than in the absence of an exogenously added phosphodiesterase inhibitor. Additions of a cAMP analog subsequent to the VIP-induced alkali secretion fail to induce any further increase in alkalinization. These results provide evidence for the action of VIP as a hormonal up regulator of alkali excretion in the turtle urinary bladder.

Topics: 1-Methyl-3-isobutylxanthine; Acid-Base Equilibrium; Acidosis; Animals; Calcitonin; Cyclic AMP; Eating; Electric Conductivity; Hydrogen-Ion Concentration; In Vitro Techniques; Neurotensin; Parathyroid Hormone; Secretin; Thionucleotides; Turtles; Urinary Bladder; Vasoactive Intestinal Peptide

Topics: Acidosis; Adenoma, Islet Cell; Aged; Diarrhea; Drug Resistance; Female; Humans; Hypokalemia; Injections, Subcutaneous; Kidney Failure, Chronic; Male; Motilin; Neurotensin; Octreotide; Pancreatic Neoplasms; Pancreatic Polypeptide; Somatostatin; Vasoactive Intestinal Peptide

Topics: Acidosis; Adenoma, Islet Cell; Diarrhea; Female; Gastrointestinal Hormones; Humans; Hypokalemia; Middle Aged; Pancreatic Neoplasms; Syndrome; Vasoactive Intestinal Peptide

A case of adult ganglioneuroma-pheochromocytoma with an associated watery diarrhea syndrome is reported. High levels of vasoactive intestinal peptide (VIP) were found in preoperative serum and in tumor tissue. The serum VIP levels fell to normal, and the watery diarrhae syndrome completely ceased following removal of the tumor. In addition to containing VIP, the tumor was rich in catecholamines, and calcitonin. Peptide hormone-containing extracts and catecholamine extracts from the tumor both activated the adenyl cyclase system and increased lipolytic activity in a preparation of isolated rat fat cells. The findings in this patient further link VIP with neural crest tissues, and suggest the importance of determining catecholamine levels in patients with the watery diarrhea syndrome.

Topics: Acidosis; Adenylyl Cyclases; Adipose Tissue; Adult; Calcitonin; Catecholamines; Diarrhea; Female; Ganglioneuroma; Gastrointestinal Hormones; Humans; Hypokalemia; In Vitro Techniques; Pheochromocytoma; Retroperitoneal Neoplasms; Syndrome; Vasoactive Intestinal Peptide