Superior mesenteric ganglion neural modulation of ovarian angiogenesis, apoptosis, and proliferation by the neuroactive steroid allopregnanolone

Structure 1. Reasons are given for believing that the methods used to produce the classical Golgi network cannot be relied upon to give an accurate picture of the structure of the Golgi element during life. 2. In this investigation reliance has been placed chiefly on vital observations and on the results of the formal-sudan-black technique. Sudan black is a colouring agent with an intense affinity for lipoids,1 whether ‘masked’ or not. 3. The Golgi element was studied in the following cells: (1) the primary spermatocyte and early spermatid of the common snail, Helix aspersa; (2) the absorptive cell of the intestinal epithelium of the smooth or common newt, Triturus vulgaris ; (3) the nerve cell of the anterior mesenteric ganglion of the rabbit, Oryctolagus cuniculus. 4. In its fully developed condition, the Golgi element of diverse cells consists of four parts: (1) the ‘neutral-red vacuoles’; (2) the dense lipoid-containing substance, generally in close relation to the vacuoles in the form of strands, ‘lepidosomes’, caps, crescents, rings, or complete investments; (3) the diffuse lipoid-containing substance, which fills all the space in the Golgi element not occupied by the other constituents; (4) the Golgi-product, which arises in the vacuoles and is the result of the synthesis achieved by the Golgi element.

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Circumferential, not longitudinal, colonic stretch increases synaptic input to mouse prevertebral ganglion neurons

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00292.2003 ◽

2003 ◽

Vol 285 (6) ◽

pp. G1129-G1138 ◽

Cited By ~ 19

Author(s):

Steven M. Miller ◽

J. H. Szurszewski

Keyword(s):

Synaptic Input ◽

Muscle Tension ◽

Circular Muscle ◽

Longitudinal Axis ◽

Muscle Layer ◽

Intraluminal Pressure ◽

Colon Wall ◽

Mesenteric Ganglion ◽

Ganglion Neurons

The relationship between longitudinal and circular muscle tension in the mouse colon and mechanosensory excitatory synaptic input to neurons in the superior mesenteric ganglion (SMG) was investigated in vitro. Electrical activity was recorded intracellularly from SMG neurons, and muscle tension was simultaneously monitored in the longitudinal, circumferential, or both axes. Colonic intraluminal pressure and volume changes were also monitored simultaneously with muscle tension changes. The results showed that the frequency of fast excitatory postsynaptic potentials (fEPSPs) in SMG neurons increased when colonic muscle tension decreased, when the colon relaxed and refilled with fluid after contraction, and during receptive relaxation preceding spontaneous colonic contractions. In contrast, fEPSP frequency decreased when colonic muscle tension increased during spontaneous colonic contraction and emptying. Manual stretch of the colon wall to 10-15% beyond resting length in the circumferential axis of flat sheet preparations increased fEPSP frequency in SMG neurons, but stretch in the longitudinal axis to 15% beyond resting length in the same preparations did not. There was no increase in synaptic input when tubular colon segments were stretched in their long axes up to 20% beyond their resting length. The circumferential stretch-sensitive increase in the frequency of synaptic input to SMG neurons persisted when the colonic muscles were relaxed pharmacologically by nifedipine (2 μM) or nicardipine (3 μM). These results suggest that colonic mechanosensory afferent nerves projecting to the SMG function as length or stretch detectors in parallel to the circular muscle layer.

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