Reproductive-state dependent changes in saccular hair cell density of the vocal male plainfin midshipman fish

The auditory system of the plainfin midshipman fish (<i>Porichthys notatus</i>) is an important sensory system used to detect and encode biologically relevant acoustic stimuli important for survival and reproduction including social acoustic signals used for intraspecific communication. Previous work showed that hair cell (HC) density in the midshipman saccule increased seasonally with reproductive state and was concurrent with enhanced auditory saccular sensitivity in both females and type I males. Although reproductive state-dependent changes in HC density have been well characterized in the adult midshipman saccule, less is known about how the saccule changes during ontogeny. Here, we examined the ontogenetic development of the saccule in four relative sizes of midshipman (larvae, small juveniles, large juveniles, and nonreproductive adults) to determine whether the density, total number, and orientation patterns of saccular HCs change during ontogeny. In addition, we also examined whether the total number of HCs in the saccule differ from that of the utricle and lagena in nonreproductive adults. We found that HC density varied across developmental stage. The ontogenetic reduction in HC density was concurrent with an ontogenetic increase in macula area. The orientation pattern of saccular HCs was similar to the standard pattern previously described in other teleost fishes, and this pattern of HC orientation was retained during ontogeny. Lastly, the estimated number of saccular HCs increased with developmental stage from the smallest larvae (2,336 HCs) to the largest nonreproductive adult (145,717 HCs), and in nonreproductive adults estimated HC numbers were highest in the saccule (mean ± SD = 28,479 ± 4,809 HCs), intermediate in the utricle (mean ± SD = 11,008 ± 1,619 HCs) and lowest in the lagena (mean ± SD = 4,560 ± 769 HCs).

Download Full-text

Kiss1 Neurons Drastically Change Their Firing Activity in Accordance With the Reproductive State: Insights From a Seasonal Breeder

Endocrinology ◽

10.1210/en.2014-1472 ◽

2014 ◽

Vol 155 (12) ◽

pp. 4868-4880 ◽

Cited By ~ 8

Author(s):

Masaharu Hasebe ◽

Shinji Kanda ◽

Hiroyuki Shimada ◽

Yasuhisa Akazome ◽

Hideki Abe ◽

...

Keyword(s):

Fluorescent Protein ◽

Resting Membrane Potential ◽

Reproductive State ◽

Firing Patterns ◽

State Dependent ◽

Channel Expression ◽

Physiological Analysis ◽

Seasonal Breeder ◽

Green Fluorescent

Kisspeptin (Kiss) neurons show drastic changes in kisspeptin expression in response to the serum sex steroid concentration in various vertebrate species. Thus, according to the reproductive states, kisspeptin neurons are suggested to modulate various neuronal activities, including the regulation of GnRH neurons in mammals. However, despite their reproductive state-dependent regulation, there is no physiological analysis of kisspeptin neurons in seasonal breeders. Here we generated the first kiss1-enhanced green fluorescent protein transgenic line of a seasonal breeder, medaka, for histological and electrophysiological analyses using a whole-brain in vitro preparation in which most synaptic connections are intact. We found histologically that Kiss1 neurons in the nucleus ventralis tuberis (NVT) projected to the preoptic area, hypothalamus, pituitary, and ventral telencephalon. Therefore, NVT Kiss1 neurons may regulate various homeostatic functions and innate behaviors. Electrophysiological analyses revealed that they show various firing patterns, including bursting. Furthermore, we found that their firings are regulated by the resting membrane potential. However, bursting was not induced from the other firing patterns with a current injection, suggesting that it requires some chronic modulations of intrinsic properties such as channel expression. Finally, we found that NVT Kiss1 neurons drastically change their neuronal activities according to the reproductive state and the estradiol levels. Taken together with the previous reports, we here conclude that the breeding condition drastically alters the Kiss1 neuron activities in both gene expression and firing activities, the latter of which is strongly related to Kiss1 release, and the Kiss1 peptides regulate the activities of various neural circuits through their axonal projections.

Download Full-text

Mucosal Immunity and Liver Metabolism in the Complex Condition of Lactation Insufficiency

Journal of Human Lactation ◽

10.1177/0890334420947656 ◽

2020 ◽

Vol 36 (4) ◽

pp. 582-590

Author(s):

Courtney B. Betts ◽

Alexandra Quackenbush ◽

Weston Anderson ◽

Nicole E. Marshall ◽

Pepper J. Schedin

Keyword(s):

Clinical Practice ◽

Mucosal Immunity ◽

Scientific Inquiry ◽

World Health ◽

Postpartum Women ◽

Human Breast ◽

Reproductive State ◽

Growth Requirements ◽

State Dependent ◽

The World

Lactation insufficiency is variously defined and includes the inability to produce milk, not producing enough milk to exclusively meet infant growth requirements, and pathological interruption of lactation (e.g., mastitis). Of women with intent-to-breastfeed, lactation insufficiency has been estimated to affect 38%–44% of newly postpartum women, likely contributing to the nearly 60% of infants that are not breastfed according to the World Health Organization’s guidelines. To date, research and clinical practice aimed at improving feeding outcomes have focused on hospital lactation support and education, with laudable results. However, researchers’ reports of recent rodent studies concerning fundamental lactation biology have suggested that the underlying pathologies of lactation insufficiency may be more nuanced than is currently appreciated. In this article, we identify mucosal biology of the breast and lactation-specific liver biology as two under-researched aspects of lactation physiology. Specifically, we argue that further scientific inquiry into reproductive state-dependent regulation of immunity in the human breast will reveal insights into novel immune based requirements for healthy lactation. Additionally, our synthesis of the literature supports the hypothesis that the liver is an essential player in lactation—highlighting the potential that pathologies of the liver may also be associated with lactation insufficiency. More research into these biologic underpinnings of lactation is anticipated to provide new avenues to understand and treat lactation insufficiency.

Download Full-text

Correlation between the hair cell density and the auditory threshold in the white rat

Hearing Research ◽

10.1016/0378-5955(80)90010-6 ◽

1980 ◽

Vol 3 (1) ◽

pp. 91-93 ◽

Cited By ~ 15

Author(s):

Hynek Burda ◽

Luboš Voldřich

Keyword(s):

Hair Cell ◽

Cell Density ◽

Auditory Threshold

Download Full-text

A distributed dopamine-gated circuit underpins reproductive state-dependent behavior in Drosophila females

10.1101/2021.07.24.453623 ◽

2021 ◽

Author(s):

Ariane C Boehm ◽

Anja B Friedrich ◽

Paul Bandow ◽

K.P. Siju ◽

Sydney Hunt ◽

...

Keyword(s):

Internal State ◽

Brain Regions ◽

Neural Pathways ◽

Reproductive State ◽

Behavioral Screening ◽

Whole Brain ◽

State Dependent ◽

Dependent Behavior ◽

Output Neurons ◽

And Behavior

Motherhood induces a drastic, sometimes long-lasting, change in internal state and behavior in most female animals. Here, we show that a mating-induced increase in olfactory attraction of female Drosophila flies to nutrients relies on interconnected neural pathways in the two higher olfactory brain regions, the lateral horn (LH) and the mushroom body (MB). Using whole brain calcium imaging, we find that mating does not induce a global change in the activity of the whole brain nor of entire brain regions, suggesting specific neuronal or network changes in the olfactory system. Systematic behavioral screening and electron microscopy (EM) connectomics identify two types of LH output neurons required for the attraction of females to polyamines -one of them previously implicated in the processing of male pheromones. In addition, we characterize multiple MB pathways capable of inducing or suppressing polyamine attraction, with synaptic connections to the identified LH neurons and a prominent role for the β′1 compartment. Moreover, β′1 dopaminergic neurons are modulated by mating and are sufficient to replace mating experience in virgins inducing the lasting behavioral switch in female preference. Taken together, our data in the fly suggests that reproductive state-dependent expression of female choice behavior is regulated by a dopamine-gated distributed learning circuit comprising both higher olfactory brain centers.

Download Full-text

Seasonal Plasticity of Auditory Saccular Sensitivity in the Vocal Plainfin Midshipman Fish, Porichthys notatus

Journal of Neurophysiology ◽

10.1152/jn.00236.2009 ◽

2009 ◽

Vol 102 (2) ◽

pp. 1121-1131 ◽

Cited By ~ 40

Author(s):

Joseph A. Sisneros

Keyword(s):

Breeding Season ◽

Hair Cells ◽

Adaptive Plasticity ◽

Advertisement Call ◽

Reproductive State ◽

Advertisement Calls ◽

Porichthys Notatus ◽

Reproductive Females ◽

Plainfin Midshipman

The plainfin midshipman fish, Porichthys notatus, is a seasonally breeding species of marine teleost fish that generates acoustic signals for intraspecific social and reproductive-related communication. Female midshipman use the inner ear saccule as the main acoustic endorgan for hearing to detect and locate vocalizing males that produce multiharmonic advertisement calls during the breeding season. Previous work showed that the frequency sensitivity of midshipman auditory saccular afferents changed seasonally with female reproductive state such that summer reproductive females became better suited than winter nonreproductive females to encode the dominant higher harmonics of the male advertisement calls. The focus of this study was to test the hypothesis that seasonal reproductive-dependent changes in saccular afferent tuning is paralleled by similar changes in saccular sensitivity at the level of the hair-cell receptor. Here, I examined the evoked response properties of midshipman saccular hair cells from winter nonreproductive and summer reproductive females to determine if reproductive state affects the frequency response and threshold of the saccule to behaviorally relevant single tone stimuli. Saccular potentials were recorded from populations of hair cells in vivo while sound was presented by an underwater speaker. Results indicate that saccular hair cells from reproductive females had thresholds that were ∼8 to 13 dB lower than nonreproductive females across a broad range of frequencies that included the dominant higher harmonic components and the fundamental frequency of the male's advertisement call. These seasonal-reproductive-dependent changes in thresholds varied differentially across the three (rostral, middle, and caudal) regions of the saccule. Such reproductive-dependent changes in saccule sensitivity may represent an adaptive plasticity of the midshipman auditory sense to enhance mate detection, recognition, and localization during the breeding season.

Download Full-text