BACKGROUND: The atrial natriuretic peptide (ANP) is a peptide hormone that is mainly produced in the cardiocytes of the atria and auricles, where it is stored within secretory granules. AIM OF THE STUDY: The aim of the present work was to analyze the effects of pre- and postnatal protein malnutrition on weight gain, the size of the heart and the number and sizes of the ANP-granules in the cardiocytes of the rat's right auricle. This study was conducted on 21-day-old rats from mothers exposed to 73% protein restriction during the gestation and lactation and on age-matched control animals. At this stage, both control and protein-deprived animals were killed by a lethal intraperitonial injection of sodic pentobarbital. The weight and the size of the heart were determined and ANP-granules of auricular cardiocytes were examined by transmission electron microscopy and ultrastructural morphometry. RESULTS: Protein deprivation of the mother throughout pregnancy, and the mother and unweaned rat pups in the first 21 postnatal days reduced the weights of pups to about 60% of the normally fed group. The weight and size of the heart were also reduced, by about 50%. Despite this, perinatal malnutrition did not significantly affect the numbers of ANP-granules/field in the cardiocytes. However, there was a small but significant reduction in the sizes of granules. CONCLUSION: It is concluded that ANP-granules are protected from loss even when there is a substantial reduction in body weight and organ size caused by protein deprivation.
BACKGROUND: The atrial natriuretic peptide (ANP) is a peptide hormone that is mainly produced in the cardiocytes of the atria and auricles, where it is stored within secretory granules. AIM OF THE STUDY: The aim of the present work was to analyze the effects of pre- and postnatal protein malnutrition on weight gain, the size of the heart and the number and sizes of the ANP-granules in the cardiocytes of the rat's right auricle. This study was conducted on 21-day-old rats from mothers exposed to 73% protein restriction during the gestation and lactation and on age-matched control animals. At this stage, both control and protein-deprived animals were killed by a lethal intraperitonial injection of sodic pentobarbital. The weight and the size of the heart were determined and ANP-granules of auricular cardiocytes were examined by transmission electron microscopy and ultrastructural morphometry. RESULTS: Protein deprivation of the mother throughout pregnancy, and the mother and unweaned rat pups in the first 21 postnatal days reduced the weights of pups to about 60% of the normally fed group. The weight and size of the heart were also reduced, by about 50%. Despite this, perinatal malnutrition did not significantly affect the numbers of ANP-granules/field in the cardiocytes. However, there was a small but significant reduction in the sizes of granules. CONCLUSION: It is concluded that ANP-granules are protected from loss even when there is a substantial reduction in body weight and organ size caused by protein deprivation.
Authors: Mario Mateus Sugizaki; Maeli Dal Pai-Silva; Robson Francisco Carvalho; Carlos Roberto Padovani; Alessandro Bruno; André Ferreira Nascimento; Flávio Ferrari Aragon; Ethel Lourenzi Barbosa Novelli; Antonio Carlos Cicogna Journal: Int J Cardiol Date: 2005-12-13 Impact factor: 4.164
Authors: Romeu R de Souza; Vanessa C de Oliveira; Tania Cristina P Curi; Diogo C Maldonado Journal: Clinics (Sao Paulo) Date: 2014-08 Impact factor: 2.365