The concentration of choline into specific regions of the thoracic ganglion in B-methylcholine fed houseflies

Abstract

When larvae of the housefly, Musca domestica, are reared on a diet in which most of the choline has been replaced by a choline analogue, B-methylcholine, the small amount of choline available to the insect is largely taken up into the nervous system where it is incorporated into phosphatidylcholine and acetylcholine. Using autoradiographic techniques it is shown that, in the thoracic ganglion, the phosphatidylcholine component of this preferentially accumulated choline is not evenly distributed throughout the tissue but that a well-defined pattern of patches of silver grains is found over certain areas of the neuropile. Underlying this pattern are axons and glial processes structurally indistinguishable from the axons and glia of adjacent areas which show a much lighter autoradiographic reaction. It is concluded that the axons which produce this high density of silver graining are cholinergic and have a high affinity for choline.

Physical dependence and tolerance development to sustained low concentrations of morphine in mice

“…The results of the daily urinary excretion study were consistent with previous reports on mice and rats (Howes & Schwope 1976;Kosersky & Ryan 1978;Kosersky & Howes 1978). The urinary excretion of lac, in the urine.…”

“…The pellets used have mostly contained 75-100 mg morphine aIkaloid/pellet. We have used naloxone-induced jumping and changes in hot-plate latency to examine the development of physical dependence and tolerance in mice to relatively low concentrations of morphine from a newly developed sustained-release preparation (Howes & Schwope 1976;Kosersky & Ryan 1978).…”