NO LOSS OF SOMATOSTATIN-IMMUNOREACTIVE NEURONS IN THE HIPPOCAMPAL DENTATE HILUS OF ALCOHOL-WITHDRAWAL-KINDLED RATS

The neuropeptide somatostatin has been suggested to play a role in sei zure genesis, electrical kindling and the neurotoxic effects of alcoho l. The purpose of the present experiment was to study somatostatin-imm unoreactive (SS-IR) neurons in hippocampus during alcohol-withdrawal k indling. Alcohol-withdrawal kindling was performed by subjecting male Wistar rats to seven weekly episodes consisting of 2 days of severe al cohol intoxication and 5 days of alcohol withdrawal. Then the kindled animals (multiple withdrawal group) and a single withdrawal group, whi ch was fed isocalorically with the kindled animals during episodes 1-7 , were exposed to 4 days of severe alcohol intoxication (episode 8). D uring the following withdrawal, the seizure activity was observed 9-15 h after last alcohol dose, in order to subdivide the animals from the se two groups into groups with and without seizures. Subsequently, SS- IR neurons were visualized immunocytochemically and counted in the hil us of the dentate gyrus (hippocampus). The number of SS-IR neurons per unit area of the hilus was neither affected by a single nor by multip le episodes of alcohol withdrawal. We therefore concluded that a loss of these neurons is not involved in the development of alcohol-withdra wal-kindled seizures.