Vasoactive intestinal polypeptide receptors in rat cerebral vessels: an autoradiographic study.

1. Localization and pharmacological properties of the vasoactive intestinal polypeptide (VIP) receptors in rat circle of Willis arteries and in the arteries of pial-arachnoid membrane were studied using light microscope autoradiography combined with radioreceptor binding techniques. 2. [125I]-VIP was specifically bound to sections of rat cerebral arteries with a dissociation constant value of 0.5 nM and a binding site density of 80 fmol mg protein-1. Radioreceptor binding experiments revealed that the binding characteristics of [125I]-VIP were consistent with the labelling of specific VIP receptors. The rank order of potency of various substances tested to inhibit [125I]-VIP binding was the following: VIP greater than peptide histidine methionine greater than secretin greater than glucagon. 3. Light microscope autoradiography revealed the localization of [125I]-VIP binding sites in the medial layer of circle of Willis and pial arteries. Quantitative determination of [125I]-VIP binding site density in the different circle of Willis arteries demonstrated a higher accumulation of silver grains in the anterior than in the posterior cerebral arteries. Pial arteries are richer in VIP receptor sites than circle of Willis arteries. 4. These results suggest that the physiological neurogenic vasodilation elicited by VIP on cerebral arteries is mediated by the interaction with specific receptor sites located primarily within cerebral vessels structures involved in the control of cerebrovascular resistances

Model of Interacting Stem Networks for Solving Problems of Topological Resilience of Complex Systems

Advanced network models for solving security problems of complex systems has been analyzed. For further development of the approach previously called comprehensive network lace, a new topological description of complex systems — composite stem model has been proposed. Concomitant classification of offensive actions has been presented

LATE INFANTILE CEROID-LIPOFUSCINOSES - AN ULTRASTRUCTURAL-STUDY

The aim of the present study is to investigate further the ultrastructural skin patterns in five cases of late infantile ceroid-lipofuscinosis: two of these were classic forms, the others were variants. Ultrastructural examinations of skin biopsies revealed the presence of characteristic cytosomes: typical lipofuscin, consisting of osmiophilic granular materials, curvilinear bodies, and fingerprint bodies. Different ultrastructural profiles were found simultaneously in each case, without a significant prevalence of any specific one, and were often associated with lipid droplets. These inclusions were found in several epidermal and dermal cells. A different degree of involvement of the myelinated sheaths in the five cases was observed. This difference could be genetically determined or perhaps related to different stages of the disease. The findings demonstrate the involvement of clinically unaffected skin and confirm the relevance of electron microscopic studies in diagnosing these disorders. In fact, recognition of typical ultrastructural changes is a valuable diagnostic tool that can be used in supplementing clinical and electrophysiological examinations, especially when the metabolic error is unknown and no diagnostic biochemical assay is available

The Role of SHOX Gene in Idiopathic Short Stature: an Italian Multicenter Study

If we exclude the patients with Leri- Weill syndrome who presented a SHOX gene deletion in 5.4%, in our cohort of patients with ISS the incidence of SHOX gene point mutations was very low (1.5%), suggesting that the presence of mesomelia, minor skeletal abnormalities, and eventually subtle radiographic signs are essential for requiring genetic analysis properly