RESUMEN
Major differences in elemental and water content in cells of rat papillae have been reported by investigators using the frozen hydrated/frozen dried method versus that using external standards for x-ray microanalysis. These differences could not be ascribed to either cryosectioning at warmer temperatures or to the analytical algorithm used by either group. In this study, six paired left and right renal papillae were subjected to x-ray analysis. The frozen hydrated/frozen dried method was used on undipped papilla, while both methods were applied simultaneously to contralateral papillae dipped in albumin standard. No significant differences were seen between the physiologic state of the left and right kidneys prior to freezing. Our results demonstrated two major problems with application of an albumin peripheral standard: 1) albumin dipping significantly changed elemental and water content in papillary collecting duct cells, epithelial cells and interstitium, but interstitial cells were not affected; 2) the peripheral albumin standard itself also changed water and elemental content in a direction consistent with movement of Na and Cl from tissue to standard, and water from standard to tissue.
Asunto(s)
Microanálisis por Sonda Electrónica/métodos , Médula Renal/análisis , Albúminas , Animales , Agua Corporal/análisis , Liofilización , Congelación , Masculino , Ratas , Ratas Endogámicas , Conservación de TejidoRESUMEN
Major differences in elemental and water content in cells of rat papillae in antidiuresis have been reported using x-ray microanalysis. The reason for these reported differences in unknown. In order to determine if the differing microprobe techniques used in these reports could account for the differences measured, we analyzed elemental concentrations in rat proximal tubule cells using both methods simultaneously on the same cells. Both methods provided comparable results. Furthermore, no differences in element or water content of proximal tubule cells cryosectioned with albumin at -53 degrees C and those cells cryosectioned at -80 degrees C were seen. Therefore, the differing values previously reported for elemental analysis of rat kidney cannot be ascribed to either cryosectioning at a warmer temperature or to the analytical algorithm used by either group.
Asunto(s)
Microanálisis por Sonda Electrónica/métodos , Túbulos Renales Proximales/análisis , Albúminas , Animales , Agua Corporal/análisis , Liofilización , Congelación , Túbulos Renales Proximales/ultraestructura , Microscopía Electrónica de Rastreo , Ratas , Ratas Endogámicas , Conservación de TejidoRESUMEN
Elemental (Na, P, S, Cl, K, Ca, Mg) composition and water content of neurons and glial cells of the leech (Macrobdella decora) were determined by x-ray microanalysis of frozen hydrated and dried section techniques. Results are reported as elemental mass fractions (mass/mass) and water content as percent mass. Specific cell compartments and cell types had distinct elemental patterns and water content which suggests that chemical composition of specific cell types is unique and may represent an expression of cell differentiation analogous to morphological specialization. Water content of cells was also cell specific and ranged from 55% (neurons) to 90% (vacuolated zone of glial cells). K and Na were present in concentrations greater than predicted by ion-selective microelectrode measurements, indicating that not all the K and Na were simultaneously accessible to such electrodes.