Automatic vessel segmentation and quantification of the rat aortic ring assay of angiogenesis.

BACKGROUND: Pharmacologic control of angiogenesis is a promising new approach to the treatment of a variety of pathologic conditions including cancer. The recently developed in vitro rat aortic ring model provides a simple, reproducible assay for discovering angiogenic agonists and antagonists. However, quantification of results in this assay is time consuming, tedious, and subjective, because it involves visual inspection of images and manually counting the newly formed microvessels extending from the cultured aortic ring. This report describes an automated image analysis-based procedure for quantification of this assay that overcomes these difficulties. EXPERIMENTAL DESIGN: The designed image processing algorithm segments the vessels from gray scale images. A high-pass filter is used, and the results are separated into nonvascular and vessel compartments based on object size and shape. Quantification relies on identification of vessels intersecting a closed transect set a fixed distance from the aortic ring. The number and the total area of these vessels are determined. The entire operation has been automated and packaged in an application called Vessels. RESULTS: The correlation between computer-determined vessel area/vessel number and visual microvessel count is high (r2 = 0.91 and r2 = 0.86, respectively). CONCLUSION: Vessels offers high-speed, fully automatic batch processing including production of a hard copy for documentation. The application runs on the Apple family of computers. On a Quadra 800, the application can process approximately 30 images/hour, which is approximately 2.5 times faster than manual quantification of this assay.

3-(1-Indolinyl)benzylamines: a new class of analgesic agents.

An extensive series of 3-(1-indolinyl)benzylamines and related compounds was synthesized and tested for analgesic activity. After a detailed study of structure-activity relationships, 3-(1-indolinyl)benzylamine (2b) was selected for further investigation as the most interesting member of this novel class of compounds. It was active in both the phenylquinone writhing and tail-flick assays for analgesic activity. No motor deficits were observed in the rotorod test, and 2b was found to be free of any other effects on the central nervous system. The compound did not bind to opiate receptors, since it was inactive in inhibiting the stereospecific binding of [3H]naloxone in rat brain homogenates. Thus, 3-(1-indolinyl)benzylamine represents a novel analgesic with an unusual chemical structure and biological profile.

Novel tetracyclic spiropiperidines. 4. Synthesis and pharmacological evaluation of spiro- and 6,7-dihydrospiro[benzo[b]pyrrolo[3,2,1-jk][1,4]benzodiazepine-2 (1H),4'-piperidine]s.

A previously described series of 1-arylspiro[indoline-3,4'-piperidine]s was reported by us to possess significant antidepressant properties. This biological activity was found to be at a maximum among those compounds bearing an ortho substituent (e.g., NH2 as in 1) in the pendant aryl ring. In order to explore further this "ortho effect", we synthesized cyclic analogues of type 3 and 4 in which the position of the o-NH2-substituted aryl group is conformationally restricted and defined. When tested for antidepressant activity by tetrabenazine ptosis prevention in mice, it was found that restriction of rotation of the pendant o-aminophenyl group in these rigid analogues resulted in a loss of antidepressant properties. However, analgesic activity was retained and even improved by this molecular constraint.

7-(Aminoacyl) and 7-(aminoalkyl) derivatives of 1,2,6,7-tetrahydroindolo[1,7-ab][1,5]benzodiazepines as potential antidepressant agents.

The synthesis of 7-(aminoacyl) and 7-(aminoalkyl) derivatives of 1,2,6,7-tetrahydroindolo[1,7-ab][1,5]benzodiazepines is described. These compounds were evaluated for antidepressant activity by their ability to inhibit tetrabenazine-induced ptosis in mice. Many compounds were found to be active in this animal model, and structure-activity relationships are discussed. Two analogues in particular, one from the 7-(aminoacyl) series (13) and one from the 7-(aminoalkyl) series (26), were of comparable potency to the antidepressant drugs desipramine and amitriptyline.