Intracellular pH in frog skin: Effects of Na sup + , volume, and cAMP

Journal Article · Fri Jul 01 00:00:00 EDT 1988 · American Journal of Physiology; (USA)

OSTI ID:7007743

Civan, M M; Cragoe, Jr, E J; Peterson-Yantorno, K ^[1]

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1. Univ. of Pennsylvania School of Medicine, Philadelphia (USA) Merck Sharp Dohme Research Laboratories, West Point, PA (USA)

Single skins were analyzed by {sup 31}P-nuclear magnetic resonance (NMR) spectroscopy during alternative perfusion with control and experimental solutions. Intracellular (pH{sub c}) and extracellular (pH{sub o}) pH were monitored by measuring the spectral frequencies of intracellular P{sub i} and external methylphosphonate, respectively. Base-line pH{sub c} was 7.20 {plus minus} 0.02 (SE) when pH{sub o} was 6.99 {plus minus} 0.02. A 4-acetamido-4{prime}-isothiocyanostilbene-2,2{prime}-disulfonic acid (SITS)-inhibitable, HCO{sup {minus}}{sub 3}-dependent alkaline shift in pH{sub c} can be elicited by replacing external Cl{sup {minus}} by gluconate or sulfate. The authors now report that this effect is observed even in sodium-free media. The substitution of gluconate for external Cl{sup {minus}} has also been reported to shrink cell volume. This shrinkage can be minimized by replacing Cl{sup {minus}} with gluconate during perfusion with hypotonic, rather than isotonic, media. Conducted in this manner, the anionic substitution produced a much smaller alkaline shift in pH{sub c}. In the presence of the Na-H antiport blocker 5-(N-methyl-N-isobutyl)amiloride (MIA), restoration of external Na{sup +} did not increase pH{sub c}. Adenosine 3{prime},5{prime}-cyclic monophosphate (cAMP) also alters pH{sub c}. The data suggest that frog skin regulates pH{sub c} by the parallel operation of Na-H and Na{sup +}-independent Cl-HCO{sub 3} antiports. Cell volume and cAMP may play regulating roles in this epithelium.

• OSTI ID: 7007743
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 255:1; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID CARBONATES
ALKALI METAL COMPOUNDS
AMP
AMPHIBIANS
ANIMAL TISSUES
ANIMALS
AQUATIC ORGANISMS
BIOLOGICAL EFFECTS
BODY
CATIONS
CHARGED PARTICLES
CHEMICAL SHIFT
CHLORINE
ELEMENTS
EPITHELIUM
ESTERS
FROGS
HALOGENS
HORMONES
IONS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MEMBRANE TRANSPORT
NONMETALS
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUCLEOTIDES
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANS
PEPTIDE HORMONES
PH VALUE
PHOSPHORUS 31
PHOSPHORUS ISOTOPES
PHYSIOLOGY
PITUITARY HORMONES
RESONANCE
SKIN
SODIUM COMPOUNDS
STABLE ISOTOPES
SULFONIC ACID ESTERS
TISSUES
VASOPRESSIN
VERTEBRATES
VOLUME