Animals ; Basilar Artery ; Brain Ischemia ; pathology ; Brain Stem ; blood supply ; Cats ; Medulla Oblongata ; blood supply

AIMObservations on medullary ischemia region, the morphology of neurons and changes of respiration and blood pressure were made, in order to give evidences on how medullary ischemia affects respiration and circulation and give some advices on how to protect from it.

METHODSUsing cats as the experimental animals, the different parts of the basilar artery trunk were ligated. The changes in the density of blood vessels, the morphology of neurons in the brainstem, the electromyogram (EMG) of the diaphragm and the blood pressure of the femoral artery were investigated.

RESULTSThe density of blood vessels notably decreased in the medulla after ligating the basilar artery trunk. The ischemic range induced by ligation of the different parts of the basilar artery trunk overlapped, mainly locating in the medulla rostral to the obex. The soma were swelled and the Nissl bodies decreased in some of neurons in the ischemic region of medulla. The duration of inspiration (T1) and expiration (TE) shortened, respiratory frequency (RF) increased, and mean blood pressure (MBP) decreased in the experimental groups (P < 0.05).

CONCLUSIONThere is an obvious overlap of the areas in which blood supplied by different parts of the basilar artery trunk. Medullary ischemia can involve in changes of respiration and blood pressure. The ischemic damage of neurons in the medulla might be the structural basis of the changes in the respiratory and circulatory functions.

Animals ; Basilar Artery ; Blood Pressure ; Brain Ischemia ; physiopathology ; Cats ; Medulla Oblongata ; pathology ; Respiration ; Respiratory System ; blood supply ; physiopathology

Medial medullary infarction is usually manifested as hypoglossal palsy, limb weakness, impairment of proprioception, and oculomotor disturbance. We report a case with the unusual presentation of sensory ataxia. A 71 year-old male presented with ataxia and disequilibrium. Bilateral dysmetria, truncal ataxia, Upbeat nystagmus, and impaired vibration and position sense were the clinical features. However, weakness of the limbs, tongue, or face was not definite. MRI revealed bilateral lesion in the medullary tegmentum, and cortical potentials of somatosensory evoked response were absent. Recovery was fair after treatment. According to the literature, motor weakness is a cardinal manifestation in medial medullary infarction, and there has been no reported case presented as sensory ataxia preserving motor power. Current development of diagnostic tools would contribute to define a variety of clinical manifestations, topography, vascular concomitants, and prognosis in medial medullary infarction.
Aged ; Ataxia/*etiology ; Cardiovascular Diseases/diagnosis ; Case Report ; Cerebral Infarction/*complications/*diagnosis ; Diagnosis, Differential ; Human ; Magnetic Resonance Imaging ; Male ; Medulla Oblongata/*blood supply ; Syndrome