Intrauterine Devices—Development, Evaluation, & Program Implementation

amines. In the early 1960's, Hillarp, Falck, and their co-workers developed the basic technique for visualizing amine-containing neurons. Treating freeze-dried tissue sections with dry formaldehyde vapor brings about condensation of the amino group of the biogenic amines with the formaldehyde. A new conjugated ring is formed, and the product fluoresces with different excitation and emission maxima for the catecholamines, serotonin, and histamine. In the first article, T. Hokfelt and his co-workers describe the use of the Vibratome, which enables sectioning of fixed or unfixed material without previous embedding. Other papers demonstrate the value of fluorescence histochemistry beyond its original use for neuronal pathway determination. Owman and his co-workers present work showing short adrenergic neurons in the vas deferens and uterine cervix. Unlike the classical postganglionic sympathetic neurons, these neurons have their cell bodies in peripheral ganglia located close to the structures they innervate. Other research combined fluorescence histochemistry with pharmacologic manipulations. The work includes studies of estrogendependent norepinephrine levels in uterine adrenergic neurons, regeneration of sympathetic neurons following treatment with 6-hydroxydopamine, and the correlation of cold-restraint stress and gastric ulceration in rats with decreased peripheral and elevated hypothalamic catecholamine fluorescence. Ligation experiments demonstrated the cervical sympathetic nerves as an apparent source of vagal catecholamine fibers; the two nerve bundles lie alongside one another, and the sympathetic trunk donates fibers to the vagus nerve. Ligation techniques also indicated the rate of axonal transport of catecholamines in rat sciatic nerve. Clinical applications of fluorescence histochemistry are foreshadowed in the finding of an abnormal distribution of catecholamines in the axons of aganglionic rectum from patients with Hirschprung's disease. Drug effects on adrenergic neurons were also studied. Guanethidine, for example, produced long-lasting damage to adrenergic neurons. Relatively low doses of guanethidine impaired neuronal amine uptake in rats for 6 months. The neurons supplying the male reproductive system were especially affected. The papers in this volume were presented at the Scandinavia-Japan Seminar on Amine Fluorescence Histochemistry held in Kyoto, Japan, in August 1972. The book is handsomely printed with right-justified text and fine quality black-and-white photographs. It is debatable whether the result compensates for the 2-year publication lag. Only a few paragraphs were devoted to the recent revolutionary advance of the glyoxylic acid method used in place of formaldehyde fluorescence. The glyoxylic acid method increases the sensitivity for catecholamines and indoleamines to permit visualization of nonterminal portions of axons. The technique has enabled much greater resolution in neuronal pathway determination [see 0. Lindvall and A. Bjorklund, Acta Physiol. Scand. Suppl. 412 (1974)].