PERINATAL UNDERNUTRITION: CHANGES IN CENTRAL OPIATE RECEPTORS DENCITY

SILVIA KADEMIAN ; MARIELA F. PEREZ; ELIZABETH KELLER

NUTRITIONAL NEUROSCIENCE

MANEY PUBLISHING

Año: 2002 vol. 5 p. 53 - 57

1028-415X

The present work sought to study the binding properties of central m-opiate receptors in whole brain and in different central areas in adult rats undernourished at perinatal age. Rats were undernourished with a hypoproteic diet containing 8% casein from day 14 of gestation until 50 days of age. The animals were thereafter fed a balanced commercial chow until 140 days of age. At this time point the experiments started. 3H-D-Ala2, N-Me- Phe4, Gly5-ol-enkephalin (3H-DAMGO) was used to selectively label the m-receptors. The results obtained demonstrated that perinatal undernutrition induced, in the adult animal, a decreased m-receptors density (Bmax) both in whole brain as well as in midbrain, without significant changes in affinity. In addition, no changes were found in m-specific binding in the cortex of these undernourished animals. Taking into account that recent evidences from our laboratory have demonstrated a lower stress-induced analgesia following exposure to different stressful situations in rats undernourished in early life, the present findings seem to suggest that this lower analgesic response could be due, at least in part, to a lower density of m-opiate receptors in the brain.m-opiate receptors in whole brain and in different central areas in adult rats undernourished at perinatal age. Rats were undernourished with a hypoproteic diet containing 8% casein from day 14 of gestation until 50 days of age. The animals were thereafter fed a balanced commercial chow until 140 days of age. At this time point the experiments started. 3H-D-Ala2, N-Me- Phe4, Gly5-ol-enkephalin (3H-DAMGO) was used to selectively label the m-receptors. The results obtained demonstrated that perinatal undernutrition induced, in the adult animal, a decreased m-receptors density (Bmax) both in whole brain as well as in midbrain, without significant changes in affinity. In addition, no changes were found in m-specific binding in the cortex of these undernourished animals. Taking into account that recent evidences from our laboratory have demonstrated a lower stress-induced analgesia following exposure to different stressful situations in rats undernourished in early life, the present findings seem to suggest that this lower analgesic response could be due, at least in part, to a lower density of m-opiate receptors in the brain.3H-D-Ala2, N-Me- Phe4, Gly5-ol-enkephalin (3H-DAMGO) was used to selectively label the m-receptors. The results obtained demonstrated that perinatal undernutrition induced, in the adult animal, a decreased m-receptors density (Bmax) both in whole brain as well as in midbrain, without significant changes in affinity. In addition, no changes were found in m-specific binding in the cortex of these undernourished animals. Taking into account that recent evidences from our laboratory have demonstrated a lower stress-induced analgesia following exposure to different stressful situations in rats undernourished in early life, the present findings seem to suggest that this lower analgesic response could be due, at least in part, to a lower density of m-opiate receptors in the brain.4, Gly5-ol-enkephalin (3H-DAMGO) was used to selectively label the m-receptors. The results obtained demonstrated that perinatal undernutrition induced, in the adult animal, a decreased m-receptors density (Bmax) both in whole brain as well as in midbrain, without significant changes in affinity. In addition, no changes were found in m-specific binding in the cortex of these undernourished animals. Taking into account that recent evidences from our laboratory have demonstrated a lower stress-induced analgesia following exposure to different stressful situations in rats undernourished in early life, the present findings seem to suggest that this lower analgesic response could be due, at least in part, to a lower density of m-opiate receptors in the brain.m-receptors. The results obtained demonstrated that perinatal undernutrition induced, in the adult animal, a decreased m-receptors density (Bmax) both in whole brain as well as in midbrain, without significant changes in affinity. In addition, no changes were found in m-specific binding in the cortex of these undernourished animals. Taking into account that recent evidences from our laboratory have demonstrated a lower stress-induced analgesia following exposure to different stressful situations in rats undernourished in early life, the present findings seem to suggest that this lower analgesic response could be due, at least in part, to a lower density of m-opiate receptors in the brain.m-receptors density (Bmax) both in whole brain as well as in midbrain, without significant changes in affinity. In addition, no changes were found in m-specific binding in the cortex of these undernourished animals. Taking into account that recent evidences from our laboratory have demonstrated a lower stress-induced analgesia following exposure to different stressful situations in rats undernourished in early life, the present findings seem to suggest that this lower analgesic response could be due, at least in part, to a lower density of m-opiate receptors in the brain.m-specific binding in the cortex of these undernourished animals. Taking into account that recent evidences from our laboratory have demonstrated a lower stress-induced analgesia following exposure to different stressful situations in rats undernourished in early life, the present findings seem to suggest that this lower analgesic response could be due, at least in part, to a lower density of m-opiate receptors in the brain.m-opiate receptors in the brain.