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Details the changes in the constitution of the International Society of Nephrology (ISN). Composition of the ISN Executive Committee; Expansion of the Council of the Society; Purpose of the changes; Overview of the amended constitution.

Presents the International Society of Nephrology's 1999 Jean Hamburger Award to Isidore S. Edelman, a physician. Professional accomplishments and contributions; Educational background; Awards received.

Presents the report of the International Society of Nephrology's President-Elect for 1999. Key goals; Challenges facing the nonprofit organization; Primary mission of the organization.

Reprints the speech of the president of the International Society of Nephrology at the First World Congress of Nephrology held on October 13, 2001. Meeting agenda; History of the society; Previous meetings of the organization.

Cl- channels in basolateral TAL membranes: XIII. Heterogeneity between basolateral MTAL and CTAL Cl- channels. Background. Antidiuretic hormone (ADH) or adenosine 3′,5′-cyclic phosphate (cAMP) analogues augment net NaCl absorption in microperfused mouse medullary thick ascending limb (MTAL) segments but not in cortical thick ascending limb (CTAL) segments. This ADH-dependent MTAL effect is due to increased apical Na+/K+/2Cl- admittance and apical K+ recycling accompanied by a rise in calculated intracellular Cl- concentrations and by a threefold rise in basolateral Cl- conductance. rbClC-Ka, a 75.2 member of the ClC family of Cl- channels, mediates net Cl- absorption in the MTAL. The gating characteristics of rbClC-Ka channels from their intracellular surfaces are, to our knowledge, unique among Cl- channels. The channels are activated by small increases in intracellular Cl- (K1/2 = 10 mm Cl-). Adenosine triphosphate plus the catalytic subunit of protein kinase A (ATP + PKA) gate rbClC-Ka when cytosolic Cl- concentrations are 25 mm. Thus, in mouse MTAL segments, ADH-dependent rises in cytosolic Cl- are primarily responsible for basolateral Cl- conductance increases. Methods. These experiments compared the properties of Cl- channels fused into bilayers from basolaterally enriched vesicles from cultured mouse CTAL cells with rbClC-Ka channels. Results. The key findings were that anti-rbClC-Ka, an antibody that recognizes and blocks rbClC-Ka, recognized and blocked basolateral Cl- channels in CTAL cells, that the extracellular faces of the CTAL channels were, like rbClC-Ka, substrate gated with a K1/2 of approximately 170 mm Cl-, and that, unlike rbClC-Ka channels, cytosolic faces of basolateral CTAL Cl-... [ABSTRACT FROM AUTHOR]

Background. Our prior data indicate that two separate but homologous basolateral chloride (Cl[sup -]) channels, mmclc-Ka and mcclc-Ka, are the principal mediators of net Cl[sup -] absorption in mouse medullary thick ascending limb (MTAL) and cortical thick ascending limb (CTAL) cells, respectively. In the present studies, we evaluated the possibility that there might be translational or post-translational suppression of mmclc-Ka and mcclc-Ka activity in CTAL and MTAL cells, respectively. Methods. Polymerase chain reaction (PCR) fragments were prepared that were highly specific for either mmclc-Ka or mcclc-Ka, the cDNAs encoding mmclc-Ka and mcclc-Ka, respectively. Results. Using reverse transcription (RT)-PCR with these highly specific products, MRNAS specific for non-homologous channel sequences in either mmclc-Ka or mcclc-Ka were present in both MTAL and CTAL cells. Conclusions. Both mouse MTAL and CTAL cells contain the MRNAS encoding mmclc-Ka and mcclc-Ka. There may be translational or post-translational suppression of mmclc-Ka activity in CTAL cells, and of mcclc-Ka activity in MTAL cells. [ABSTRACT FROM AUTHOR]

Examines the net salt absorption and potassium secretion in mouse medullary thick limbs. Description of basolateral membranes; Regulation of thick limb salt transport by antidiuretic hormone; Mechanism of antidiuretic hormone effect.

Presents an obituary for Claude Amiel, a scientists who died in August 1996 in France.