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M E Frank

Publications and source records attributed to M E Frank.

At least 55 records · Page 3Linked to original sources
PubMed1990

Taste-responsive neurons and their locations in the solitary nucleus of the hamster.

The solitary nucleus (nucleus tractus solitarii), the first central relay for taste in mammals, was studied anatomically and physiologically in the golden hamster (Mesocricetus auratus). Activity of neurons to anterior tongue stimulation with sucrose, NaCl and KCl were extracellularly recorded. Electrolytic lesions or horseradish peroxidase deposits allowed subsequent localization of recording sites. Anterior tongue taste-responsive sites were restricted to a very small part of the rostral pole of the solitary nucleus, which is about 3% of the entire nucleus. Sites were confined to the rostral-central and rostral-lateral subdivisions of Whitehead, which contain a number of morphological cell types. Some chemotopic organization was seen with multi-unit recordings, with NaCl-selective sites concentrated rostrally and sucrose- and KCl-selective sites concentrated caudally. Sites with broad sensitivity were distributed throughout the gustatory region. Single neural units showing inhibition to taste stimuli, units highly reactive to all three stimuli, and units with high spontaneous rates were seen in the solitary nucleus, as well as units that responded very selectively and had low spontaneous rates. Single units with similar response profiles to sucrose, NaCl and KCl were not segregated to separate restricted locations within the taste-reactive region; their distributions overlapped. In the hamster, neurons in the anterior tongue taste region of the solitary nucleus process taste quality information in diverse ways. Highly reactive non-specific neurons, neurons that show inhibition, and neurons with high spontaneous rates are more frequently observed in the solitary nucleus than in the afferent input fibers of the chorda tympani nerve. The small region of the rostral pole enclosing taste-responsive neurons is complexly organized in relation to taste quality and contains a number of morphological cell types whose functional role in taste is not yet known.

Action Potentials↗
PubMed1989

Self-preoccupation and general stress level as sensitizing factors in premenstrual and menstrual distress.

This study considered whether general stress level and self-preoccupation sensitize women to symptoms of menstrual and premenstrual distress and whether this effect is more pronounced for premenstrual symptoms. Equal-size categories of normal college women reporting greater distress during the premenstrual period (PD), during the menstrual period (MD), or about equally in both periods were constituted. The PD women demonstrated significantly greater self-preoccupation than either the MD or equivalent groups; they also reported higher general stress than either comparison group, although statistical reliability was not attained. However, when both sensitizing factors were introduced into the same analysis, high self-preoccupation and a high level of general stress were found only in the PD group. The present evidence suggests that stress and personality not only sensitize premenstrual symptoms in PMS women but are prominent features in normal women who report more serious symptoms during the premenstrual period.

Adolescent↗
PubMed1989

Chemosensory neuroanatomy and physiology.

Three nasal/oral sensory systems, which are anatomically and physiologically distinct, mediate smell, taste, and irritation. However, all three systems may be stimulated by food chemicals (which have "flavors" for the individual), and their receptors are located in adjacent oral and nasal cavities. The three sensory systems each have tiny cerebral cortical representations in humans, and interact with ventral forebrain areas attributed roles in affect and incentive. The complexity of these interactions makes it difficult for affected patients to identify readily which chemosensory system is malfunctioning.

Chemoreceptor Cells↗
PubMed1988

The organization of taste sensibilities in hamster chorda tympani nerve fibers.

Electrophysiological measurements of nerve impulse frequencies were used to explore the organization of taste sensibilities in single fibers of the hamster chorda tympani nerve. Moderately intense taste solutions that are either very similar or easily discriminated were applied to the anterior lingual surface. 40 response profiles or 13 stimulus activation patterns were considered variables and examined with multivariate statistical techniques. Three kinds of response profiles were seen in fibers that varied in their overall sensitivity to taste solutions. One profile (S) showed selectivity for sweeteners, a second (N) showed selectivity for sodium salts, and a third (H) showed sensitivity to salts, acids, and other compounds. Hierarchical cluster analysis indicated that profiles fell into discrete classes. Responses to many pairs of effective stimuli were covariant across profiles within a class, but some acidic stimuli had more idiosyncratic effects. Factor analysis of profiles identified two common factors, accounting for 77% of the variance. A unipolar factor was identified with the N profile, and a bipolar factor was identified with the S profile and its opposite, the H profile. Three stimulus activation patterns were elicited by taste solutions that varied in intensity of effect. Hierarchical cluster analysis indicated that the patterns fell into discrete classes. Factor analysis of patterns identified three common unipolar factors accounting for 82% of the variance. Eight stimuli (MgSO4, NH4Cl, KCl, citric acid, acetic acid, urea, quinine HCl, HCl) selectively activated fibers with H profiles, three stimuli (fructose, Na saccharin, sucrose) selectively activated fibers with S profiles, and two stimuli (NaNO3, NaCl) activated fibers with N profiles more strongly than fibers with H profiles. Stimuli that evoke different patterns taste distinct to hamsters. Stimuli that evoke the same pattern taste more similar. It was concluded that the hundreds of peripheral taste neurons that innervate the anterior tongue play one of three functional roles, providing information about one of three features that are shared by different chemical solutions.

Animals↗
PubMed1987

Persistence of taste buds in denervated fungiform papillae.

Taste buds in hamster fungiform papillae persist in an atrophic state for as long as 330 days after chorda tympani denervation or 50 days after combined chorda tympani-lingual nerve resection. Although taste bud structure depends on innervation, there is no absolute neural requirement for taste bud survival.

Animals↗
PubMed1983

Anatomy of the gustatory system in the hamster: central projections of the chorda tympani and the lingual nerve.

The sensory modalities of taste and touch, for the anterior tongue, are relegated to separate cranial nerves. The lingual branch of the trigeminal nerve mediates touch: the chorda tympani branch of the facial nerve mediates taste. The chorda tympani also contains efferent axons which originate in the superior salivatory nucleus. The central projections of these two nerves have been visualized in the hamster by anterograde labelling with horseradish peroxidase (HRP). Afferent fibers of the chorda tympani distribute to all rostral-caudal levels of the solitary nucleus. They synapse heavily in the dorsal half of the nucleus at its rostral extreme; synaptic endings are sparser and located laterally in caudal regions. These taste afferents travel caudally in the solitary tract and reach different levels by a series of collateral branches which extend medially in the the solitary nucleus, where they exhibit preterminal and terminal swellings. Taste afferent axons range in diameter from 0.2 micrometer to 1.5 micrometers. The thickest axons project exclusively to the rostral and intermediate subdivisions of the solitary nucleus; the find ones may distribute predominantly to the caudal subdivision. Afferent fibers of the lingual nerve terminate heavily in the dorsal one-third of the spinal nucleus of the trigeminal nerve and also as a dense patch in the lateral solitary nucleus at the midpoint between its rostral and caudal poles. This latter projection overlaps that of the chorda tympani. Thus the two sensory nerves which subserve taste and touch from coincident peripheral fields on the tongue converge centrally on the intermediate subdivision of the solitary nucleus. Efferent neurons of the superior salivatory nucleus were labelled retrogradely following application of HRP to the chorda tympani. These cells are located ipsilaterally in the medullary reticular formation ventral to the rostral pole of the solitary nucleus; their dendrites are oriented dorsoventrally. The efferent axons course dorsally, form a genu lateral to the facial somatomotor genu, and course ventrolaterally through the spinal nucleus of the trigeminal nerve to exit the brain ventral to the entering facial afferents.

Afferent Pathways↗
PubMed1983

Nerve fibers sensitive to ionic taste stimuli in chorda tympani of the rat.

Hypotheses about the peripheral basis for the sense of taste in mammals have been based to a considerable degree on the determined sensibilities of the nerve fibers in the chorda tympani of the rat to chemical stimulation of the anterior tongue. Yet, whether neuron types exist in this nerve, the nature of the basic mechanisms of taste reception that are tapped by this nerve and the form in which information about stimulus quality and intensity is transmitted to the central nervous system by this nerve are, at present, unresolved issues. These issues are addressed in the present study, which is a detailed analysis of the responses of rat chorda tympani nerve fibers that are sensitive to ionic stimuli; solutions applied to the anterior tongue included a range of concentrations of four chemical compounds (sucrose, sodium chloride, hydrochloric acid, and quinine hydrochloride) that represent widely different taste qualities to man or rat. Of the 44 nerve fibers sampled, 40 were stimulated most by one of the two ionic stimuli at test concentrations reported to be equally effective: 21 fibers were most responsive to 0.1 M NaCl and named N units; 19 fibers were most responsive to 0.01 M HCl and named H units. Although many N and H units responded to both HCl and NaCl, the distribution of NaCl-HCl response ratios was bimodal, indicating there are two varieties of units sensitive to ionic taste stimuli in the rat chorda tympani. Sucrose (0.5 M) affected 4 of the nerve fibers and was the most effective stimulus for 3 of them; 0.02 M quinine affected 13 of the fibers but 10 of these were H units. H units were less "specifically tuned" than N units; they were more likely to respond to several of the chemicals. Although the absolute sensitivity to NaCl in N units or to HCl in H units varied more than 10-fold, the relative effects of the four stimuli (response profiles) were generally similar for units of a given type. Exceptions occurred when H unit responses to NaCl or quinine were suppressed by prolonged effects of preceding HCl stimulation. The similarity in response profiles is reflected in high and significant correlations between responses to each pair of effective stimuli across either H or N units.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1980

Specificity of acquired aversions to taste qualities in hamsters and rats.

Nine groups of rats and 27 groups of hamsters (n = 12/group) each tasted 1 from among 27 different solutions before receiving an ip injection of apomorphine, then were tested for aversions to 4 solutions prototypic of human beings' four taste qualities (S, sucrose; N, NaCl; H, Hcl; Q, quinine hydrochloride). With most of the solutions that are described as sweet by humans employed as a conditional stimulus (CS), the rodents acquired an S aversion (exceptions occurring for some artificial sweeteners). With CSs described as either predominantly salty or sour by humans, the rodents acquired an N aversion in the former case or an H aversion in the latter case; a Q aversion was also acquired with two (including H) of the three CSs described as sour. With most of the CSs described as predominantly bitter or as having a considerable bitter component by humans, the rodents acquired a Q aversion (as well as a weaker H aversion). Considerable parallels among the taste sensations of humans, rats, and hamsters are indicated. Patterns of activity evoked across four classes of peripheral gustatory neurons (those responding best to lingual stimulation with S, N, H, or Q) in rodents when the CSs were applied to the tongue were similar to the patterns of aversions across the four test stimuli for the CSs. This suggests that these four neural channels mediate the sensations evoked by S, N, H, and Q in rats and hamsters, perhaps even in human beings.

Animals↗
PubMed1980

Effects of binary taste stimuli on the neural activity of the hamster chorda tympani.

Binary mixtures of taste stimuli were applied to the tongue of the hamster and the reaction of the whole corda tympani was recorded. Some of the chemicals that were paired in mixtures (HCl, NH4Cl, NaCl, CaCl2, sucrose, and D-phenylalanine) have similar tastes to human and/or hamster, and/or common stimulatory effects on individual fibers of the hamster chorda tympani; other pairs of these chemicals have dissimilar tastes and/or distinct neural stimulatory effects. The molarity of each chemical with approximately the same effect on the activity of the nerve as 0.01 M NaCl was selected, and an established relation between stimulus concentration and response allowed estimation of the effect of a "mixture" of two concentrations of one chemical. Each mixture elicited a response that was smaller than the sum of the responses to its components. However, responses to some mixtures approached this sum, and responses to other mixtures closely approached the response to a "mixture" of two concentrations of one chemical. Responses of the former variety were generated by mixtures of an electrolyte and a nonelectrolyte and the latter by mixtures of two electrolytes or two nonelectrolytes. But, beyond the distinction between electrolytes and nonelectrolytes, the whole-nerve response to a mixture could not be predicted from the known neural or psychophysical effects of its components.

Ammonium Chloride↗
PubMed1980

Sensitivities of single nerve fibers in the hamster chorda tympani to mixtures of taste stimuli.

Responses of three groups of neural fibers from the chorda tympani of the hamster to binary mixtures of taste stimuli applied to the tongue were analyzed. The groups displayed different sensitivities to six chemicals at concentrations that had approximately equal effects on the whole nerve. Sucrose-best fibers responded strongly only to sucrose and D-phenylalanine. NaCl-best and HCl-best fibers, responded to four electrolytes: equally to CaCl2 and nearly equally to HCl, but the former responded more to NaCl, and the latter responded more to NH4Cl. The groups of fibers dealt differently with binary mixtures. Sucrose-best fibers responded to a mixture of sucrose and D-phenylalanine as if one of the chemicals had been appropriately increased in concentration, but they responded to a mixture of either one and an electrolyte as if the concentration of sucrose or D-phenylalanine had been reduced. NaCl-best fibers responded to a mixture as if it were a "mixture" of two appropriate concentrations of one chemical, or somewhat less. But, responses of HCl-best fibers to mixtures were greater than that, approaching a sum of responses to components. These results explain effects on the whole nerve, suggest that the sensitivity of a mammalian taste receptor to one chemical can be affected by a second, which may or may not be a stimulus for that receptor, and suggest that some effects of taste mixtures in humans may be the result of peripheral processes.

Ammonium Chloride↗
PubMed1966

Effects of high incubation temperature upon the cell wall of Escherichia coli.

Hoffman, Heiner (New York University, New York, N.Y.), Jon Valdina, and Michael E. Frank. Effects of high incubation temperature upon the cell wall of Escherichia coli. J. Bacteriol. 91:1635-1637. 1966.-Escherichia coli cells grown at 45 C were found to swell when suspended in distilled water, and were broken down when subjected to egg white lysozyme. Cells grown at 37 C were unaffected by these reagents. It appears, therefore, that cultivation at the upper limits of the temperature growth range leads to cell wall damage. It is suggested that this reaction may account for the favorable therapeutic effects of artificially elevated body temperature in certain infectious diseases.

Cell Wall↗
PubMed1965

Time-Lapse Photomicrography of Lashing, Flexing, and Snapping Movements in Escherichia coli and Corynebacterium Microcultures.

Hoffman, Heiner (New York University, New York, N.Y.), and Michael E. Frank. Time-lapse photomicrography of lashing, flexing, and snapping movements in Escherichia coli and Corynebacterium microcultures. J. Bacteriol. 90:789-795. 1965.-A series of four consecutive photomicrographs of snapping by an Escherichia coli cell pair indicates that this maneuver consists initially of lashing movements of one cell unattached to the underlying surface and consequent flexion of the second cell, which is strongly attached to the underlying surface at its distal end. This is followed by a final unidirectional movement of the unattached cell which carries the attached cell with it. Lashing movements were also observed in microcultures of fusobacteria and a Corynebacterium, and photomicrographs were obtained of the latter. The observations cannot be interpreted to support the conventional hypothesis that snapping is a response to partial rupture of the capsule during cell division. A new hypothesis is suggested which is based upon motile intracellular granules that have been observed to break out of E. coli, corynebacteria, and fusobacteria cells, typically from the cell ends. Photomicrographs of the minute granules were obtained for both E. coli and the Corynebacterium.

Journal Article↗
PubMedDate not supplied

Neuron types, receptors, behavior, and taste quality.

Neurophysiological studies on chorda tympani (CT) single fibers and behavioral studies on generalization of learned aversions in hamsters (Mesocricetus auratus) are reviewed. The work on hamsters is compared to work on other species, including the laboratory rat and several primate species, including humans. This body of data demonstrates associations between response profiles of physiologically defined specialist CT neurons and behavioral stimulus generalizations on one hand, and characteristics of putative taste receptors, on the other. Response profiles of generalist CT neurons are similarly associated with receptor characteristics, but are not associated with specific behavioral discriminations. The associations of peripheral nerve data with both receptor and behavior strongly suggest specific codes for "sucrose-like" and "NaCl-like" taste qualities. Definitive conclusions regarding "patterns" or "labeled lines" requires an understanding of mechanisms of central neural processing of the several specialist and generalist taste-afferent inputs.

Animals↗