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C R Caflisch

Publications and source records attributed to C R Caflisch.

29 records · Page 2Linked to original sources
PubMed1980

In situ micropuncture study of pancreatic duct pH.

The pH and chloride concentration in the extralobular duct system of the rabbit pancreas was investigated by using glass-membrane pH microelectrodes and microsampling techniques. The response of pH microelectrodes was compared to that of a pH macroelectrode system in buffer solutions containing common interfering substances and it was found that the electrodes were insensitive to these substances. Final pancreatic juice electrolyte concentrations and osmolality were found to be similar to that observed by others. Under free-flow conditions, a significant pH gradient was found between small extralobular ducts (7.47) and final juice (8.03). This gradient was nearly obliterated on stimulation with secretin. Duct chloride concentrations were found to be similar in all duct sizes and final juice under unstimulated conditions and after stimulation with secretin. It is concluded that glass-membrane pH microelectrodes are reliable and accurate indicators of pH in this system. The present experiments suggest that the entire extralobular ductal system may participate in the secretion of an alkaline fluid.

Animals↗
PubMed1979

Exocrine ductal pCO2 in the rabbit pancreas.

An improved pCO2 microelectrode has been evaluated and used to investigate whether a significant barrier to diffusion of CO2 exists in the rabbit pancreas. The results of this study show the improved Carter and Caflisch pCO2 microelectrode to be an accurate and reliable tool for measuring pancreatic venous and ductal pCO2. The similarities between pCO2 values from the pancreatic ducts and small pancreatic veins suggest that there is no barrier to CO2 diffusion between small veins and exocrine ducts in the rabbit pancreas, and that ductal pCO2 is probably strongly influenced by the CO2 tension of the small pancreatic blood vessels.

Animals↗
PubMed1978

Manufacture and utilization of antimony pH electrodes.

A new technique for manufacturing single-barreled and double-barreled antimony pH microelectrodes is described. The results of investigations into the accuracy of antimony as a pH sensor disclosed that the pH-voltage response is: 1) within the physiologic range, principally the result of the hydrogen ion activity of the solution in which the voltage is being developed, 2) in part, qualitatively anion-dependent, 3) modified by the presence of significant amounts of at least carbon dioxide, oxygen, and nitrogen gases, and 4) markedly offset by fluctuations in temperature. Our results further indicate that the accuracy of antimony as a pH sensor is determined by the quality of the calibration procedure. We conclude that if the antimony electrode is to accurately determine the pH of a biological fluid, the pH calibration solutions must closely resemble the unknown biological fluid with respect to temperature, PO2, PN2, and types of buffering anions. A calibration procedure is described which can minimize errors with antimony pH estimations when measuring the pH of proximal tubular fluid of the mammalian kidney.

Animals↗
PubMedDate not supplied

Effect of a nonsteroidal antiandrogen, flutamide on intraluminal acidification in rat testis and epididymis.

Flutamide, a pure antiandrogen was administered to intact adult male rats to study the effect of altered availability of hormones on in situ pH, PCO2 and bicarbonate concentration ([HCO3-]) of seminiferous tubules, proximal caput, middle caput, middle corpus, and proximal cauda epididymidis. The weights of the epididymis and ventral prostate as well as the plasma testosterone level showed antiandrogenic effects of flutamide. Relative to controls, flutamide elevated significantly in situ pH in proximal caput, middle caput, middle corpus and proximal cauda epididymidis but not in seminiferous tubules. In situ PCO2 values in the above segments, after flutamide, were indistinguishable from controls and from each other but all values remained significantly higher than systemic arterial blood PCO2. Flutamide treatment did not change the [HCO3-] in systemic arterial blood or seminiferous tubules but increased markedly the values in proximal caput and middle caput. The results of the present studies support the view that luminal acidification in the rat epididymis is under androgen control and may be important for sperm maturation and storage.

Animals↗