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Biomedical subjects

T W Schoultz

Publications and source records attributed to T W Schoultz.

5 recordsLinked to original sources
PubMed1977

Microscopic analysis of early histopathological spinal cord alterations following trauma in normal and cathecholamine-depleted cats.

The progressive histopathological sequence over the first 3 hr after a 400 g-cm blunt injury to the spinal cord of catecholamine (CA)-intact and CA-depleted cats is described. Norepinephrine levels were measured in all animals. The experiments were designed to determine the role of CA in progressive hemorrhagic necrosis of the spinal cord by removing CA from one group of animals prior to trauma. A second group of CA-intact animals was subjected to identical experimentally-induced trauma. Upon analysis of the histopathological changes, it appears that the sequential nature of the development of hemorrhagic necrosis is both qualitatively and quantitatively similar in both experimental groups. The general conclusion is drawn that catecholamines in greater than normal amounts are present at the lesion site after trauma, but these catecholamines are probably not involved in the process of central hemorrhagic necrosis.

Animals↗
PubMed1976

Norepinephrine levels in traumatized spinal cord of catecholamine-depleted cats.

This study was designed to elucidate the origin of norepinephrine (NE) measured in spinal cord following trauma. In normal cats the NE concentration at the lesion site increased 63% over control 1 h following experimentally produced blunt trauma (400 g-cm). Spinal cords of adrenalectomized cats were also traumatized, but there was no increase in NE levels 1 h post-trauma. Spinal cord NE levels in these animals were not significantly different from normal or adrenalectomized non-injured controls. In the absence of one of the major peripheral sources of catecholamine, the adrenal medulla, our decreased NE levels prompt us to disagree with the hypothesis that NE measured in injured spinal cord is liberated from intrinsic neuronal systems. It is likely that the mechanism of NE accumulation is directly related to increased circulating levels of NE. The authors speculate on a possible reason for the conflicting results obtained by different laboratories in this area of research.

Adrenalectomy↗
PubMed1975

Mechanical transduction in the Golgi tendon organ: a hypothesis.

Morphological evidence, gained from light and electron microscopy, has shown that the unmyelinated terminal branches of the Ib afferent fiber innervating the Golgi tendon organ (GTO) lie within the spaces between braids of collagen. Based on empirical data it is proposed that force applied to a muscle's tendon will straighten these collagen braids and cause compressional deformation of the axon branches trapped between them. The mechanical events, which are presumed to occur within the GTO, appear to explain how it may function as a biological force transducer under static loading conditions. The mechanical principal described for the GTO may be a primitive and wide-spread biological mechanism employed by certain types of sensory receptors that function as position (and force) detectors.

Animals↗