Parathyroid hormone (PTH) transiently increases urinary excretion of the lysosomal enzyme, N-acetyl-beta-D-glucosaminidase, which is distributed mainly in proximal tubules. The response is reduced in pseudohypoparathyroidism (PHP) type I, which is characterized by target-organ resistance to PTH. Evidenced by normal calcium resorption, distal tubule sensitivity to PTH has been believed to be nor...

We studied the mechanisms of K(+) transport in cells from isolated and perfused collecting tubules and ducts from the mesonephric kidney of the toad Bufo bufo. Cells were impaled with microelectrodes across the basal cell membrane. The basolateral membrane potential (V(bl)) depolarized upon change of bath [K(+)] from 3 to 20 mmol l(-1) demonstrating a large K(+) conductance in this membrane. In...

We previously reported that rabbit renal cortical collecting tubules can secrete bicarbonate in vitro (i.e., there can be net transport from bath to lumen, causing the concentration in the lumen to increase). Net bicarbonate secretion was observed most often when rabbits had been pretreated with NaHCO(3) and were excreting alkaline urine before being killed for experiments. The purpose of the p...

Renal infection rarely occurs following the intravenous injection of Gramnegative bacilli into normal animals. If, however, the kidney has been damaged by either direct trauma or ureteral ligation, an increased susceptibility to infection can be demonstrated."' In this regard, studies have shown that the location of the site of injury within the kidney is important in determining alterations of...

Gentamicin (GM) is a widely used antibiotic but shows renal toxicity. We produced a serum against GM (anti-GM) conjugated to bovine serum albumin with N-(gamma-maleimidobutyryloxy)succinimide. The antiserum was monospecific for GM and did not cross-react with the analog streptomycin, tobramycin, kanamycin, or amikacin. The antiserum also detected glutaraldehyde-fixed GM, and this enabled us to ...

In previous studies, when rabbit cortical collecting ducts were studied under standard conditions in vitro, bicarbonate transport was conditioned by the acid-base status in vivo of the animals from which the tubules were obtained. The collecting ducts absorbed bicarbonate if the animals were acidotic (from ammonium chloride administration), but they secreted bicarbonate if the animals were alka...

The large macroand microscopic variability in kidney morphology among fish makes it difficult to build a “universal” understanding on its function and structure [1]. Species-specific studies are thus needed. Thus, morphological study of brown trout trunk kidney was performed, considering potential seasonal and gender effects. Three-year-old specimens of both genders were collected at four stage...