ELECTRON MICROSCOPIC OBSERVATION ON THE ULTRASTRUCTURE OF PITUICYTES OF RATS AFTER PAIN STIMULATION / 解剖学报

ABSTRACT

Twenty adult male rats, weighing 200～300 g were divided into 3 groups: (1) Six. animals were stimulated through two electrodes fixed on the tail to produce somatic pain.(2) Six animals were stimulated by increasing pressure in the stomach through an air balloon to cause visceral pain. And 8 animals served as control.All the animals were sacrificed and their neurohypophysis were fixed in 4％ glutaraldehyde and 1％ OsO_4 successively. Their section were cut with an LKB microtome and observed under H 500 electron microscope.The experimental results summarized as follows:1. The bodies of pituicytes under the pain stimulation were hypertrophied. The rough endoplasmic reticulum, polyribosomes and mitochondria were increased. The Golgi complex was well developed. There were numerous elliptical vesicles appearing in the cytoplasm of pituicytes.2. The number of large lipid masses was increased while the processes of pituicytes engulfed the degenerative neurosecretory terminal into them and the pituicyte digted it finally.3. Neurosecretory granules were decreased but the synaptic small vesicles were increased in the dilated parts of neurosecretory fibers after the pain stimulation.4. The continuous network of perivascular space and interstitial space between the dilated parts of neurosecretory fibers were widened.