Renal intraspecific variation along an aridity gradient detected by new renal indices in a desert herbivorous rodent

TEJO RIQUELME PATRICIA; DÍAZ GABRIELA; ANDINO NATALIA; BORGHI CARLOS

JOURNAL OF EXPERIMENTAL ZOOLOGY PART A-ECOLOGICAL GENETICS AND PHYSIOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2014 vol. 321 p. 348 - 356

1932-5223

Mammals that live in arid and semiarid environments in South America present physiological mechanisms that enable them to conserve water. Body water is lost through the kidneys, lungs, skin and intestines. Regarding renal adaptation for water conservation, several indices have been used to estimate the capacity of the kidneys to produce a maximum urine concentration. Most studies were conducted at an inter-specific level, with only few performed at the intraspecific level. In this work, we compare renal function and morphology among five populations of Southern mountain cavy, Microcavia australis, present along an aridity gradient. We hypothesized that individuals from drier zones would present morphological and functional renal features that indicate a greater capability to conserve body water. These features were studied considering the classical indices (RMT, PMT, PMA, and RMA) and three new indices that consider area measurements; the latter showed to be more adequate to reflect intraspecific differences. Thus, the morphological modifications of kidneys, i.e., the greater areas of renal inner medulla, are related to the aridity gradient where populations of Southern mountain cavy occur.