15. Uric acid and urate cells distribution in the Neotropical apple-snail Pomacea canaliculata (Caenogastropoda, Ampullariidae)

GIRAUD-BILLOUD M, VEGA IA, CASTRO-VAZQUEZ A

Merlo, San Luis

Congreso; XXII Reunión Anual de la Sociedad de Biología de Cuyo; 2004

Sociedad de Biología de Cuyo

We studied the correlation between tissue concentrations of uric acid (mg of uric acid per g of tissue dry mass) and the topographical distribution of crystalloid-containing cells (“urate cells”) in organs of P. canaliculata. Basal concentrations of uric acid (range of mean values: 0.2-2.2 mg/g) were only found in those organs devoid of urate cells (propodium, posterior kidney, uterine gland), while high concentrations (range: 33.8-198.7 mg/g) were found in those with numerous urate cells arranged in typical perivascular sleeves (midgut gland, testis, lung, and the coiled part of the intestine). Also, high uric acid concentrations were correlated with conglomerates of urate cells that were not integrated to typical perivascular tissue, and that were found in (1) the intestinal mucosa, particularly in the typhlosole of the coiled intestine; (2) the mesentery; and (3) the aortic ampulla. In the latter place, urate cells were organized in conspicuous subendothelial nodules. Besides those locations, the anterior kidney and the gill showed intermediate uric acid concentrations (range: 6.7-9.0  mg/g), which were correlated with the presence of urate cells in the sleeves surrounding the adjoining vessels but not in the organs themselves. This study is part of a broader program aimed to disclose the physiological significance of uric acid storage in these snails.