Fast blue and diamidino yellow as retrograde tracers in peripheral nerves: efficacy of combined nerve injection and capsule application to transected nerves in the adult rat.

Capsule application of Diamidino Yellow (DY) to the cut end of the sciatic nerve immediately followed by capsule application of Fast Blue (FB) resulted in approximately 95% double-labelled dorsal root ganglion neurones (DRGn) and motoneurones (Mn). Nerve injection of DY followed either immediately or 2 months later by capsule application of FB resulted in approximately 90% double-labelled DRGn and Mn, indicating that DY and FB label similar populations of DRGn and Mn, and that insignificant DY fading occurred during this period. Inversing the order of application, however, i.e. nerve injection of FB followed immediately by capsule application of DY, resulted in double labelling in only approximately 10% of the DRGn and Mn. These percentages increased to 70% of the DRGn and 60% of the Mn when the FB injection was followed 1 or 2 months after by the DY application, indicating that DY uptake is blocked by recent administration of FB. The results indicate that DY and FB might be useful for sequential labelling before and after nerve injury as a tool to investigate the accuracy of sensory and motor regeneration.

Representations of hindlimb digits in rat dorsal root ganglia.

The distribution in dorsal root ganglia of neurones that innervate the distal tips of the hindlimb digits in the rat were mapped after subcutaneous injections of the fluorescent tracers Fast Blue, Diamidino Yellow, and Fluoro-Gold into different digits. Three-dimensional reconstruction was used to describe the intraganglionic distribution of neurones labelled from different digits. Labelled neurones were found mainly in the L3-L5 ganglia. The distribution in ganglia and the number of neurones labelled from each digit varied considerably between cases, but mean numbers of labelled neurones were similar for the different digits. Neurones in L3 tended to innervate medial digits and neurones in L5 tended to innervate lateral digits, but most neurones from any digit were found in L4. Although overlap was considerable, the three-dimensional reconstruction showed tendencies of neurones to be distributed in restricted territories within the dorsal root ganglia. This was especially clear in ganglion L5, where digit IV was found to be represented more rostrally than digit V. The results indicate that primary afferent neurones that innervate the hindlimb digits are represented by a crude rostrocaudal somatotopic organisation both among and within lumbar dorsal root ganglia.

Sciatic and femoral nerve sensory neurones occupy different regions of the L4 dorsal root ganglion in the adult rat.

The topographical distribution of sciatic and femoral nerve sensory neuronal somata in the L4 dorsal root ganglion of the adult rat was mapped after retrograde tracing with one or two of the dyes Fast Blue, Fluoro-Gold, or Diamidino Yellow. The tracers were applied to the proximal transected end of either nerve alone, or from both nerves in the same animal using separate tracers. Three-dimensional reconstructions of the distribution of labelled neurones were made from serial sections of the L4 dorsal root ganglion which is the only ganglion that these two nerves share. The results showed that with little overlap, femoral nerve neurones distribute dorsally and rostrally whereas sciatic nerve neurones distribute medially and ventrally. This finding indicates the existence of a somatotopical organisation for the representation of different peripheral nerves in dorsal root ganglia of adult animals.

Efficacy of the fluorescent dyes Fast Blue, Fluoro-Gold, and Diamidino Yellow for retrograde tracing to dorsal root ganglia after subcutaneous injection.

The present study was designed to investigate the efficacy of the fluorescent dyes Fast Blue (FB), Fluoro-Gold (FG), and Diamidino Yellow (DY) for retrograde tracing of lumbar dorsal root ganglia after their subcutaneous injection into different hindlimb digits. Injections of equal volumes (0.5 microl) of 51% FB or 2% FG resulted in similar mean numbers of sensory neurones labelled by each tracer. Injection of equal volumes (0.5 microl) of FB or FG in a single digit followed 10 days later by a second injection of the same volume of 5% DY into the same digit resulted in similar mean numbers of labelled sensory neurones for each of the three tracers. Furthermore, on average, 75% of all the FB-labelled cells and 74% of all FG-labelled cells also contained DY. Repeating the same experiment with an increased volume of DY (1.5 microl) resulted in an increase in the mean number of double-labelled profiles to 82 and 84% for FB and FG, respectively. The results show that FB, FG and DY label similar numbers of cutaneous afferents and that a high level of double labelling may be obtained after sequential injections in digits. These properties make them suitable candidates in investigations where a combination of tracers with similar labelling efficacies is needed.

Comparative morphological study of the normal human lens and the cataract by scanning electron microscopy.

The human lens is an important part of the anterior segment of the eye because of its transparency and its refractive power. These special features of the lens depend on the special arrangement of its cellular elements, the lens fibres. The morphology of these fibres, their cellular integrity, the interfibrillar junction mechanisms and their spatial arrangement deteriorate with age because of complex biochemical and biophysical phenomena. All these factors cause a general disorder in the morphology of the various layers of the lens that will finally lead to the loss of the characteristic transparency and the concomitant development of a cataract.

Increased cardiac endocrine activity after common bile duct ligation in the rabbit. Atrial endocrine cells in obstructive jaundice.

OBJECTIVE: This study investigated the pathogenesis of water and sodium metabolism derangements in obstructive jaundice. SUMMARY BACKGROUND DATA: Obstructive jaundice is associated with hypodipsia, depletion of extracellular water, alterations of the water and sodium regulating hormones, and an increased incidence of renal failure. Plasma atrial natriuretic factor (ANF) increases after common bile duct ligation in the rabbit. The present study was designed to investigate ANF-secreting cardiac atrial cells in this animal model. METHODS: Plasma ANF and the percentage of atrial cells staining for ANF were determined in jaundiced and sham-operated rabbits at 24 (group OJ-24, n = 11; group SO-24, n = 5) and 72 hours (group OJ-72, n = 11; group SO-72, n = 5) after surgery. The atrial ANF content was also determined. RESULTS: Plasma ANF was higher in jaundiced animals than in controls both at 24 (63 +/- 44 fmol/mL vs. 17 +/- 10 fmol/mL, p < 0.02) and at 72 hours (73 +/- 49 fmol/mL vs. 12 +/- 11 fmol/mL). In the two OJ groups, the percentage of positive ANF cells per 200-power field in the right atrial appendage was higher than in the SO groups both at 24 (62 +/- 11% vs. 31 +/- 12%, p < 0.003) and at 72 hours (56 +/- 18% vs. 31 +/- 12%, p < 0.01). Similar results were obtained in the right auricular wall. The percentage of positive ANF cells was significantly higher in the left atrium in which significant differences between the OJ and SO groups were also noted. The right atrial ANF content was higher in the OJ than in SO groups (437 +/- 323 pmol/mg of protein vs. 83 +/- 44 pmol/mg of protein). CONCLUSIONS: Cardiac endocrine activity is increased in experimental obstructive jaundice. ANF may be involved in the pathogenesis of the renal and water and sodium metabolic disturbances present in this disease.

Effect of ascitic liquid on growth in vitro of embryoid bodies derived from teratocarcinoma.

Embryoid bodies (EB) derived from teratocarcinoma (TC) OTT6050 were cultured with ascitic liquids (AL) from animals carrying 16-, 22- and 35-day evolved EB. At the same time the presence of fibronectin (FN) in AL were analyzed by immunoblotting. Results indicate the probable existence of growth-stimulatory factors for EB, as well as the presence of FN in the 22-day AL.

The sclerocorneal trabecula of the primates.

In this work, after having studied the chamber angle of 14 types of primates, we describe the sclerocorneal trabecula. They are a formation dependent on the tendinous insertion fibres of the longitudinal portion of the ciliary muscle. These trabecula consist of a reticulate area and another spongy area with some interstices that we think get bigger or smaller in size according to the degree of contraction of the ciliary muscle, thus either easing or impeding the flow of aqueous humour to Schlemm's canal.

[Comparative study of the medial longitudinal striae of the hippocampus (formerly called "nerves of Lancisi") in the fighting bull and domestic bull]. / Etude comparative des stries longitudinales médiales de l'hippocampe Lanciennement "nerfs de lancisi") chez le taureau de combat et le taureau domestique.

In this paper a comparative study is made of stria longitudinalis medialis in the fighting bull and domestic bull. This nervous bundles are more developed in the former, and their connections with the Gyrus dentatus and Hippocampus are demonstrated. The structural differences observed between both animals could be related with the mechanisms that control the aggressive behaviour.

Scanning electron microscope study of the communications between the anterior chamber and the sinus venosus sclerae in primates.

We have studied the morphology of the anatomical structures that permit communication between the anterior chamber and the sinus venosus sclerae. Examination of the posterior or inner wall of this canal, represented by the sclerocorneal trabecula, in 15 species of primates and 5 adult humans, has enabled us to observe the existence of some small orifices or stomata that are the outermost part of the so-called Sondermann's canals, which in our opinion are made by the successive confluence of the interstices worked in the interior of the sclerocorneal trabecula by means of contraction of the longitudinal portion of the ciliary muscle.

Recording of chick embryo movements and their correlation with joint development.

Chick embryo movements were picked up, by means of a vibration-recording technique, from the 5th day of incubation until the moment of hatching, and correlated with histological observations of the main joints. A close relationship could be demonstrated between the dates on which the first movements can be recorded and the commencement of joint formation.

Cytodifferentiation of mouse visceral endoderm: study with a teratocarcinoma antiserum.

In this work we separated homogeneous embryoid bodies (EB); this population is composed of only endodermal vesicles of a visceral type. These EB were used to immunize rabbits. After absorption, the antisera were analyzed immunohistochemically in sections of 7.5- and 9-day-old mouse embryos, which showed a selective reaction to visceral endoderm. The cytodifferentiation of the visceral endoderm was studied.

The facial motor nucleus of the dog. II. Morphometric analysis.

In this study, an area of 953.2 micron 2, a diameter of 36.7 micron and a circularity factor of 0.74 have been established for the neurons of the facial motor nucleus of the dog. Significant differences (p less than 0.01) were observed by comparing the means of some of the parameters determined in the six cytoarchitectonic subdivisions of the facial motor nucleus described in a previous study. Moreover, the neurons tend to increase in size in the caudocranial direction.

The facial motor nucleus of the dog. I. Cytoarchitectonic subdivisions and cytology.

A study of the facial motor nucleus of the dog by means of cytoarchitectonic and computer-aided three-dimensional reconstruction methods has been made. We identified three regions in this structure: lateral, intermediate and medial. Taking into account the different patterns of neuron aggregation, the following subdivisions were noted in the first, the ventrolateral and dorsolateral subnuclei; in the second, the intermediate subnucleus, and in the third, the ventromedial, intermediate-medial and dorsomedial subnuclei. Their cytological characteristics are described.