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The effects of a stable prostacyclin mimetic, iloprost (30 nmol/l), and of indomethacin (3 mumol/l) on ischemia-plus-reperfusion-induced changes in myocardial hemodynamics and sympathetic nerve function were examined in Langendorff-perfused rabbit heart isolated except for the postganglionic sympathetic cardiac nerves. Noradrenaline overflow was measured during an initial 1-min period of nerve stimulation (S1), compared with an identical stimulation (S2) made after 2 h of low-flow ischemia followed by a 30-min reperfusion period. Myocardial catecholamine content of left ventricular tissue was also measured. Pretreatment with iloprost, indomethacin, or vehicle began 10 min before ischemia. Global ischemia plus reperfusion reduced myocardial catecholamine content by 19% (vehicle), and the reduction was greater in indomethacin-pretreated hearts (37%, p less than 0.05), whereas iloprost increased tissue noradrenaline 18% above vehicle control (p less than 0.05). Initially, nerve stimulation-induced noradrenaline overflow ranged from 213 to 247 pmoles, and was significantly reduced after ischemia and reperfusion, the difference (S1-S2) being 198 pmoles (vehicle) and 117 pmoles (indomethacin), but only 44 pmoles after iloprost pretreatment (all groups p less than 0.01). In addition, iloprost improved the recovery of active systolic pressure development, coronary perfusion and left ventricular compliance on reperfusion, whereas a tendency toward further deterioration was observed in indomethacin-pretreated hearts. The results suggest that iloprost may protect both myocardial muscle and nerve cells from ischemia-plus-reperfusion injury. Preservation of myocardial catecholamine levels and sympathetic nerve responsiveness may contribute to improved recovery of reperfused ischemic myocardium.

There are two somatosensory areas in the telencephalon of the pigeon which receive an input from the spinal somatosensory system: one in the rostral Wulst which consists of the three hyperstriatal layers (h. accessorium (HA), h. intercalatus superior (HIS) and h. dorsale (HD] and one in the caudal telencephalon (neostriatum caudale (NC), neostriatum intermedium (NI) and hyperstriatum ventrale (HV]. Recordings of evoked single unit or multi unit activity and of field potentials before and after lesions of spinal pathways at a high cervical level (C4) were made to determine the contribution of these pathways to the transmission of somatosensory signals to these telencephalic areas. The rostral Wulst area receives somatic signals only through dorsal tracts contralateral to the recording site. Inputs from the wing arise mainly through the dorsal columns (DC) and those from the leg largely through the dorsolateral funiculus (DLF). The spinal projection pathway to the caudal neostriatal area includes the dorsal tracts and parts of the lateral funiculi on both sides. There was no difference in response form between the wing and leg responses. Signals transmitted through the lateral pathways were found to elicit the earliest responses (6-13 ms, electrical stimulation) in the caudal forebrain, while signals travelling through the DC arrive later in the caudal area (about 14 ms for wing stimulation) than in the rostral Wulst area (about 9 ms). The afferent thalamic and intratelencephalic connections of the two somatosensory areas in the telencephalon of the pigeon were investigated with retrograde transport of the neuronal tracers horseradish-peroxidase (HRP) or wheatgerm agglutinated HRP (WGA-HRP), Fast Blue (FB) and Rhodamine-isothiocyanat (RITC). Small tracer-injections were made under electrophysiological control at somatosensory responsive locations. These investigations confirm the projection of the caudal part of the nucleus dorsolateralis posterior (DLPc) to the caudal area and of the nucleus dorsalis intermedius ventralis anterior (DIVA) to the rostral area. In addition, it could be shown that the NI/NC projects to the HV thus confirming the electrophysiological results reported in a companion paper (Funke 1989) that the HV is a secondary area. The integrative function of HV is supported by connections to other sensory and motor telencephalic areas. Combined injections of FB and RITC revealed a topographic projection from the DIVA to the anterior Wulst.(ABSTRACT TRUNCATED AT 400 WORDS)

22 primary intraocular malignant melanomas in the dog and 5 in the cat were classified histologically. Pigmented epithelioid cells and mixed cell type melanomas with high reticulin fiber content and areas of necrosis were associated with the highest mortality rate. Metastases were found in one case each in the dog and the cat. The average age at diagnosis was 8 years in the dog and 9 years in the cat. There was no indication that intraocular melanomas are more prevalent in certain breeds. In the dog the cases were equally distributed between the sexes, whereas in the cat males were overrepresented. The most frequent location for the tumor was the uvea anterior (ciliary body). Bilateral tumor expression was observed once in a dog. In all cases the clinical diagnosis, tumor induced secondary effects, differential diagnosis and catamnesis are given.

Two somatosensory regions in the pigeon's telencephalon were investigated electrophysiologically with recordings of field potentials as well as single- and multi-unit responses which were evoked by electrical stimulation of all four extremities or by feather movements produced with airpuffs or by hand. The outline of both areas, was studied in detail with the use of grid-like recordings of single or multi-units. One somatosensory area is located rostrally in the hyperstriatum accessorium (HA), rostral to the visual "Wulst". A caudal area comprises the medial aspects of two different cell layers: the neostriatum intermedium (NI) and adjacent neostriatum caudale (NC) as well as the overlying hyperstriatum ventrale (HV). The two areas differ considerably in their response characteristics. Field potentials of the NI/NC-HV area were more complex than those of the HA area and their shapes and latencies varied mainly in dependence of the recording site (NI, NC, HV). Multi-unit responses showed strong excitation and short latencies in NI/NC and weak excitation and longer latencies in HV. Both responses and latencies were uniform in the HA area and latencies generally longer than in NI/NC but shorter than in HV. The HA area processes somatosensory information more specifically. Its neurons have relatively small receptive fields which seem to be arranged in a somatotopic order in such a way that rostral parts of the body are represented superficially and caudal parts in deeper layers. In contrast, the NI/NC-HV area was found to be largely multimodal, receiving also auditory and visual information. Neurons in this region have large somatic receptive fields, often including one and sometimes even both sides of the body surface. A somatotopic arrangement could not be recognized. The whole body surface was representated in both areas, but there was a dominance of wing and back receptive fields in the NI/NC-HV area and leg and neck receptive fields in the HA area.