Ipsilateral

While the nigrostriatal pathways are ipsilateral some crossing occurs in fibres from the ventral tegmental AlO nucleus. These pathways are shown diagramatically in Fig. 7.1. Further details can be obtained from Moore and Bloom (1978) and Lindvall and Bjorkland (1978). The nuclei provide distinct loci for activating the dopamine systems for electrophysiological, release and behavioural studies and for their destruction by electrolytic lesion or injection of the toxin 6-hydroxydopamine (6-OHDA). 

K NRjght to left. Ipsilateral Left to right. Contralateral ... 

Figure 7.7 Dopamine-induced rotation in the rat in which one (left) nigrostriatal dopamine pathway from the substantia nigra (SN) to the caudate putamen (CP) has been lesioned by a prior injection (14 days) of 6-hydroxydopamine. Amphetamine, an indirectly acting amine, releases DA and so can only act on the right side. Since the animal moves away from the dominating active side it induces ipsilateral rotation (i.e. towards the lesioned side). By contrast, the development of postS5maptic supersensitivity to DA on the lesioned side ensures that apomorphine, a directly acting agonist, is actually more active on that side and so the animal turns away from it (contralateral rotation)...

Central/Tertiary structures The fish olfactory bulb is a fourlayered structure much as in higher vertebrates. Within the 2nd layer, the first synapse for olfactory input is on the dendrites of the mitral cells (MC). About 1000 ORN axons converge on one MC, a ratio similar to mammals. The MC output, from cells at various levels, leads into several glomeruli and receives (inhibitory) input from granule cells. The latter also innervate a distinct cell type in the MC layer of teleosts — the ruffed cells (RC), with which they have reciprocal synapses [Fig. 2.18(a)] both relay cells send ascending fibres to forebrain centres (Kosaka and Hama, 1982). The RC are unlike the MC since they are not stimulated by the ORNs directly. Their interactions (Chap. 5) may contribute to the processing of pheromonal stimuli (Zippel, 2000). The main bulbar pathways project to several nuclei in the forebrain via two ipsilateral tracts, the lateral and medial [Fig. 2.18(b)], the latter mediates sexual behaviour and the former probably other behaviours (Hara,... 

The two main olfactory tracts [Fig. 2.19(a)] comprise an ipsilateral bundle — in the lateral olfactory tract (LOT) — and some contralateral fibres in the anterior olfactory habenular tract (AOHT). The input from the MOS and AOS shows no inter-familial differences in the final brain locations, apart from minor anatomical variants (Schmidt, 1990). 

All the drugs tested in these experiments were administered (IP) at doses ranging from 3 to 10 mg/kg (except for ketamine, which was tested at 10, 30, and 100 mg/kg). All the rats used had previously turned contralaterally in response to 0.05 mg/kg apo-morphine HC1. Net ipsilateral rotations were counted in two consecutive 15-minute bins, immediately following drug (or saline) admi ni strati on. ... 

The most interesting aspects of the studies reviewed here are that the drugs having discriminative stimulus properties similar to PCP also produce ipsilateral turning and that this behavior is well correlated with both affinity for the PCP/sigma receptor and the ability to inhibit the effects of NMDA on transmitter release in the striatum. Although inhibition of NMDA-induced DA release was... 

Fessler, R.G. Sturgeon, R.D. and Meltzer, H.Y. Phencyclidine-induced ipsilateral rotation in rats with unilateral 6-hydroxy-dopamine-induced lesions of the substantia nigra. Iife Sci 24 1281-1293, 1979. 

The benefit of carotid endarterectomy for prevention of recurrent stroke has been studied previously in major trials.25,26 A recent meta-analysis has been completed that has combined these clinical trials to evaluate 6,092 patients.27 Carotid endarterectomy has been shown to be beneficial for preventing ipsilateral stroke in patients with symptomatic carotid artery stenosis of 70% or greater and is recommended in these patients. In patients with symptomatic stenosis of 50% to 69%, a moderate reduction in risk is seen in clinical trials. In all patients with stenosis of 50% to 69% and a recent stroke, carotid endarterectomy is appropriate. In other patients, surgical risk factors and surgeon skill should be considered prior to surgery. The patient should have, at a minimum, a life expectancy of 5 years, and the surgical risk of stroke and/or death should be less than 6%. Carotid endarterectomy is not beneficial for symptomatic carotid stenosis less than 50% and should not be considered in these patients. 

Local therapy of early-stage breast cancer consists of modified radical mastectomy or lumpectomy plus external-beam radiation therapy. The surgical approach to the ipsilateral axilla may consist of a full level I/II axillary lymph node dissection or a lymph node mapping procedure with sentinel lymph node biopsy. 

The extent of receptor supersensitivity after unilateral nigrostriatal lesions can be quantified by measuring the extent of rotational behavior. After selective nigrostriatal lesions have been produced in rats by injections of 6-hydroxydopamine into the substantia nigra, the number of dopamine receptors in the ipsilateral corpus striatum increases markedly, and the increase in the number of receptors may correlate with the extent of behavioral supersensitivity as monitored by rotational behavior [52]. Thus, the increase in receptor density appears to play a role in the behavioral supersensitivity of these animals. 

Axons of antennal ORCs project through the antennal nerve to enter the brain at the level of the ipsilateral antennal lobe (AL) of the deutocerebrum (52). ORC axons project from the flagellum to targets in the AL, but axons from antennal mechanosensory neurons bypass the AL and project instead to an "antennal mechanosensory and motor center" in the deutocerebrum posteroventral (with respect to the body axis of the animal) to the AL (52, 58, 64). In moths and certain other insect groups, sex-pheromonal information is processed in a prominent male-specific neuropil structure in each AL called the macroglomerular complex (MGC) (16, 52, 64, 65). 

By means of intracellular recording and staining methods, we have examined the responses of AL neurons to stimulation of the ipsilateral antenna with each of the sex pheromone components as well as partial and complete blends (75). In accordance with results of behavioral and sensory-receptor studies, components A and B are the most effective and potent sex pheromone components for eliciting physiological responses in the male-specific AL neurons. On the basis of these responses, we classified the neurons into two broad categories pheromone generalists and pheromone specialists (76). Pheromone generalists are neurons that respond similarly to stimulation of either the component A input channel or the component B input channel and do not respond differently when the complete, natural pheromone blend is presented to the antenna. In contrast, pheromone specialists are neurons that can discriminate between antennal stimulation with component A and stimulation with component B. There are several types of pheromone specialists. Some... 

Many pheromone-responsive protocerebral neurons have arborizations in the lateral accessory lobes (LALs), which are situated lateral to the central body on each side of the protocerebrum and appear to be important for processing of olfactory information (86). Each LAL is linked, by neurons with arborizations in it, to the ipsilateral superior protocerebrum as well as the lateral protocerebrum, where axons of AL... 

Sawyer TE, Bonner JA, Gould PM, et al. The impact of surgical adjuvant thoracic radiation therapy for patients with nonsmall-cell lung carcinoma with ipsilateral mediastinal lymph node involvement. Cancer 1997 80 1399-1408. 

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