The pyramidal tract of the hedgehog (Erinaceus europaeus) and its relationship with the olfactory bulb.

The pyramidal tract of the hedgehog has been investigated. The motor cerebral cortex was first located electrophysiologically and subsequently ablated. Ablation of the motor cortex did not apparently cause motor deficits. The cerebral hemisphere of the operated side, brain stem and spinal cord were removed for histological examination. The Nauta-Gygax and the horseradish peroxidase methods were employed to study the course and origin of the above mentioned tract. The pyramidal tract runs ipsilaterally in the cerebral peduncle, and does not go beyond the first cervical segments of the spinal cord (C3-C4); moreover, their fibers do not cross at spinal level. The close relation between this anatomical pathway and the olfactory bulb of the same side is also reported.

Immunolocalization of cytokeratins in some freshly fixed bovine epithelia.

Various freshly fixed bovine epithelia were studied with regard to their cytokeratin expression. The epithelia were tested by the ABC immunoperoxidase method with AE1, AE3, anti-keratin B and anti-keratin C monoclonal antibodies. While the hair follicle and nasolabial gland express both small acidic and large basic cytokeratins, the epidermal cells, sebaceous gland and mucosae appear to contain only the latter, and the mammary gland, only the former cytokeratins. Our results on fixed and paraffin embedded material are compared with those reported by others in cell cultures from human and bovine specimens.

[Update on the presence of taste buds on the laryngeal surface of the epiglottis]. / Ancora sulla presenza di calici gustativi nella faccia laringea dell'epiglottide.

Previous investigations have ascertained, according to the results obtained by Bradley et al. (1980) in the sheep, that the laryngeal surface of the epiglottis of goat and bovine is always provided with numerous taste buds. These observations have verified in other ruminant species, as the moufflon and the buffalo, the validity of the above-named datum and have ascertained that it is always inconstant in the other animal species considered (wild boar, coypu). These taste buds show a typical structure (diameter of the outer taste pore varying from 2.7 to 4.2 micron, width of the chemoreceptors varying from 30 to 60 micron and length from 27.5 to 57.5 micron). Moreover, the normal structure of the above-named taste buds is also testified by the arrangement of their innervation and particularly by the integrity of the synaptic contacts. The results of the present research have permitted a critical and more severe examination of the probable functional role of those laryngeal receptors. In fact, in the ruminants they may protect the deep airways precluding to food particles the larynx in the phase of food regurgitation.

On the collateral sesamoidean (suspensory navicular) ligament of equines: topographic relations and sensitive innervation.

The origin and course of the collateral sesamoidean (suspensory navicular) ligament of the horse and ass and its attachment to the distal sesamoid bone were studied by means of dissection. Particular attention was given to the topographic relations between this ligament and the deep digital flexor tendon. Numerous sensitive nerve endings are present in this anatomical district. The free and encapsulated nerve endings, displayed by impregnating techniques, are mostly concentrated in the ligament tract connected to the above-named tendon and close to its attachment to the distal sesamoid angle. The nerve endings are identified as typical Pacini, Pacini-like and Golgi-Mazzoni corpuscles on account of their morphological features and are found isolated, grouped to form flower-sprays, lined up along the course of a single nerve fibre or grouped to originate poikilomorphous fibres.

[Neuromuscular spindles of the extrinsic ocular musculature of the moufflon]. / I fusi neuromuscolari nella muscolatura estrinseca oculare del Muflone.

Proprioceptive innervation of moufflon extrinsic ocular musculature and m. levator palpebrae superioris was studied. Muscle spindles and Golgi tendon organs were found. The first ones are usually between 1st and 2nd order muscle fascicles. The muscle spindles are highly represented in the extrinsic ocular muscles, but less numerous in m. levator palpebrae superioris. Their number varies according to muscles and individuals. In the same subject, also the ratio between the number of the muscle spindles found in m. rectus dorsalis and that of m. levator palpebrae superioris was examined. Besides, the histological structure of the intrafusal fascicles was investigated. Particular attention was devoted to the nerve supply of the muscle spindle. By means of impregnating methods, sensory and motor endings were identified. Primary and secondary sensory endings only in a few cases showed their usual pattern: motor fibres can end in form of plates or trails. Golgi tendon organs were observed between the tendon and the muscular tissue and are always less numerous.

Coccygeus and levator ani muscles in the rabbit: morphology and proprioceptive innervation.

The Authors have studied the morphological features and the proprioceptive nervous component in the coccygeus and levator ani muscles of the rabbit, using Ruffini's and Barker-Ip's impregnations. The coccygeus muscle originates from ischiatic spine and inserts on the last three sacral vertebrae and on the first four or five caudal vertebrae. The levator ani muscle originates from the ischiatic spine and the coccygeus muscle aponeurosis and inserts directly on the caudal vertebrae 3-5 or 4-6. The proprioceptive innervation in both muscles is constituted by muscle spindles and Golgi tendon organs with a typical structure. Muscle spindles are more numerous than Golgi tendon organs and the spindle density is higher in the levator ani muscle.

Macroscopic organization and sensitive innervation of the tendinous intersection and the lacertus fibrosus of the biceps brachii muscle in the ass and horse.

The most developed and organized lamina running trough the biceps brachii muscle belly forms a well-marked tendinous intersection connecting the proximal tendon with the distal one. Moreover, the lacertus fibrosus arises from this lamina close to the distal tendon and blends with the fascia of the forearm and joins the extensor carpi radialis muscle. The nerve supply for the biceps tendinous intersection arises from the intramuscular rami of the musculo-cutaneous nerve, whereas the lacertus fibrosus is provided with some cutaneous rami of the same nerve. The biceps brachii tendinous intersection and lacertus fibrosus are provided with free and encapsulated nervous endings. The encapsulated corpuscles are represented by rare Pacini, Pacini-like and Ruffini receptors and by numerous Golgi tendon-organs. All these receptors have been studied by a topographical point of view and the role played by the proprioceptors in synchronizing shoulder, elbow and carpal joint movements both in the flexion and the extension of the limb, has been hypothesized.

Course and termination of the pyramidal tract in the pig.

To study the pyramidal tract in the pig, the motor cerebral cortex of one side was defined electrophysiologically and subsequently excised. The animals operated were killed after 7, 11 and 14 days, and the cerebral hemisphere of the operated side, brain stem and spinal cord were removed for histological examination. The pyramidal tract proved to run ipsilaterally as far as the oral extremity of the 12th cranial nerve nucleus. The decussation, which exhausted itself almost completely at the level of the rostral extremity of the 1st cervical metamere, started here. After the limit just mentioned only rare isolated fibres were visible. Along its course, the pyramidal tract sent a small number of axons to the ipsilateral and contralateral nucleus of the 7th cranial nerve, while the fibres running from the opposite side to the reticular formation and to the hypoglossal nerve nucleus, cuneatus, gracilis and trigeminal spinal tract nuclei were more numerous.

Sensory nerve endings in the peroneus tertius muscle of the ass and horse: a functional hypothesis.

The various types of sensory nerve endings found in the peroneus tertius muscle in the ass and in the horse have been studied with Ruffini's gold chloride method. Free nerve endings have been described as well as encapsulated receptors. These corpuscles are classified as Pacini-like, Ruffini's terminations and also Golgi's tendon-organs. The authors have pointed out the morphology, topography and structural characteristics of the above named nervous terminations and have hypothesized that a probable functional relation existed between these nervous corpuscles and the considered tendinous structure.

Effects of 3-acetylpyridine (3-AP) intoxication on the nervous system of mammals and birds.

The authors studied, for the first time, the effects of 3-acetylpyridine administration on the nervous system of birds. The results were compared with those obtained in a mammal not studied yet. The data achieved from the guinea-pig confirmed substantially those got from other mammals, particularly from the rat. They pointed out the constant toxic action caused by the above drug inoculation on the central nervous system. The effects on birds are quite different: 3-AP administration, even at different doses from those employed in mammals, seldom provokes lesions of the central nervous system and the appearance of alterations does not depend on the considered species.

On the presence and probable functional role of the nervous terminations located within the retractor penis muscle of some mammals.

The authors have studied the vegetative and sensitive somatic innervation of the retractor penis muscle in some domestic animals. This last component is constituted by encapsulated receptors classified as Pacini, Pacini-like, Golgi-Mazzoni's corpuscles and Krause's end bulbs (genital corpuscles). They have also emphasized the structural characteristics of the various types of nervous endings and their remarkable variability in the investigated animals. Finally, they have examined the probable functional role of these mechanicoreceptors.

On the presence, structure and probable functional role of taste buds located on the laryngeal surface of the epiglottis in some domestic animals.

The authors have performed a systematic investigation on the epiglottis to determine the number and topography of taste buds possibly present. These chemoreceptors are constantly present in the ruminants studied (goat, cattle), while their finding is always negative in the pig, horse and ass and varying in the other animal species examined. Taste buds are, in the main, fairly numerous and show typical structure in very young kids and calves. On the contrary, in adult subjects degenerated taste buds can be found and their number usually increases with age. Sometimes such pictures can be observed also in young animals. The probable functional role of chemoreceptors located on the laryngeal surface of the epiglottis has been examined.

Further observations on the innervation of the proximal sesamoidean ligament of the horse and ox.

A vegetative innervation is described for the first time in this district. On the contrary, the finding of Pacini and pacini-like corpuscles, of Golgi Mazzoni's receptors, of muscle spindles and Golgi's tendon-organs testifies the existence of a sensitive innervation in this anatomical territory. According to Karamanlidis free nervous endings are not present. All the above recorded receptors show the typical structure and can be found isolated, grouped to constitute flower-sprays, organized to form opposito-polar corpuscles or associated to originate pecilomorphic fibers. These two last findings are new for this investigated anatomical territory. Moreover, the authors have described in the ox the so-called composed corpuscles previously observed by Ottolenghi (1931) and Karamanlidis in the horse. Finally, it has been demonstrated, contrary to the data reported by Karamanlidis, that the muscle spindles located in the ligament are always supplied with a nervous annulo-spiral termination which is centrally placed in the equatorial region.

The motor and proprioceptive innervation of the retractor bulbi muscle of the lamb.

The motor and proprioceptive innervation of the retractor bulbi muscle of the lamb has been studied. The motor innovation of the muscles supplied only by the abducens never. The proprioceptive nervous fibers coming from the muscle spindles of this extraocular muscle enter the brain stem through the ophthalmic branch of the trigeminal nerve and have their perikarya in the semilunar ganglion.

[Motor and proprioceptive innervation of the retractor bulbi muscle in the lamb]. / Sulla innervazione motoria e propriocettiva del muscolo retrattore del bulbo nell'agnello.

The Authors have studied the motor and proprioceptive innervation of the retractor bulbi muscle of the lamb. The motor innervation of this muscle is supplied by the abducens nerve. The proprioceptive fibers from the muscle spindles of the retractor bulbi muscle travel in the ophthalmic branch of the trigeminal nerve and have their perikaria in the semilunar ganglion.

[The sensitive innervation of the proximal sesamoid ligament of the ox]. / Innervazione sensitiva del legamento sesamoideo prossimale del bovino.

The Authors have studied the sensitive innervation of the proximal sesamoid ligament of the ox and have found capsulated corpuscles only. Among these receptors, besides Pacini and pacini-like corpuscles, Golgi Mazzoni's corpuscles, muscle spindles and Golgi's tendon organs with a typical structure, the Authors have been described, for the first time in the ox, corpuscles constituted by numerous Pacini collected by a single capsule. It must be pointed out that the muscle spindles are always supplied by an annulo-spiral termination which is centrally placed in the equatorial region. A vegetative innervation is also present in this ligament.