HAXPES beamline PES-BL14 at the Indus-2 synchrotron radiation source

The Hard X-ray Photo-Electron Spectroscopy (HAXPES) beamline (PES-BL14), installed at the 1.5 T bending-magnet port at the Indian synchrotron (Indus-2), is now available to users. The beamline can be used for X-ray photo-emission electron spectroscopy measurements on solid samples. The PES beamline has an excitation energy range from 3 keV to 15 keV for increased bulk sensitivity. An in-house-developed double-crystal monochromator [Si (111)] and a platinum-coated X-ray mirror are used for the beam monochromatization and manipulation, respectively. This beamline is equipped with a high-energy (up to 15 keV) high-resolution (meV) hemispherical analyzer with a microchannel plate and CCD detector system with SpecsLab Prodigy and CasaXPS software. Additional user facilities include a thin-film laboratory for sample preparation and a workstation for on-site data processing. In this article, the design details of the beamline, other facilities and some recent scientific results are described.

Radiographic morphology of normal ring apophyses in the immature cervical spine

BACKGROUND

The ring apophyses of the cervical spine have a variable appearance that changes with age. The times at which they appear and fuse at each level are not fixed. In this study, we aim to detail normal ranges of appearance of these ossification centers for each age group.

MATERIALS AND METHODS

One hundred and eighty patients under the age of 21 attending the Royal Stoke University Hospital for cervical spine radiographs were retrospectively identified. The presence or absence of ring apophyses at each cervical level and whether these had undergone fusion was reported, as were the thickness, length, and craniocaudal and anteroposterior distance of the apophysis from the vertebral body. The angulation of the apophysis relative to the endplate was also noted.

RESULTS

The youngest patient in which apophyses were seen was aged 3, but apophyses were otherwise rarely seen before the age of 6. All apophyses were present from age 14, and the superior apophyses fused by the age of 18, although unfused inferior apophyses were still seen in the 20-year age group. It was observed that apophyses were rarely separated from the vertebral body by greater than 1 mm in craniocaudal distance (1%) or 2.5 mm in anteroposterior distance (2.6%) and the anterior apophysis was angulated towards the endplate in only 1% of cases.

CONCLUSIONS

We have detailed the range of normal appearances of the ring apophyses of the developing cervical spine. Cervical spine apophyseal injury is thought to be rare, but knowledge of normative morphological features should help in this diagnosis.

Characterization of leaf transcriptome, development and utilization of unigenes-derived microsatellite markers in sugarcane (Saccharum sp. hybrid)

Sugarcane (Saccharum species hybrid) is the major source of sugar (> 80% sugar) in the world and is cultivated in more than 115 countries. It has recently gained attention as a source of biofuel (ethanol). Due to genomic complexity, the development of new genomic resources is imperative in understanding the gene regulation and function, and to fine tune the genetic improvement of sugarcane. In this study, a cDNA library was constructed from mature leaves so as to develop ESTs resources which were further compared with nucleotide and protein databases to explore the functional identity of sugarcane genes. The non-redundant ESTs (unigenes) were categorized into 18 metabolic functions. The major categories were bioenergetics and photosynthesis (4%), cell metabolism (5%), development related protein (3%), membrane-related, mobile genetic elements (5%), signal transduction (2%), DNA (1%), RNA (1%) and protein (2%) metabolism, other metabolic processes (3%), transcription factors (1%), transport (4%) and proteins related to stress/defense (4%). From 540 unique ESTs, 212 simple sequence repeats were identified, of which 206 were from 463 singlets and six were mined from 77 contig sequences. A total of 540 unique EST sequences were used for SSR search of which 97 (17.9%) contained specified SSR motifs, generating 212 unique SSRs. The genes characterized in this study and the EST-derived microsatellite markers identified from the cDNA library will enrich genomic resources for association- and linkage-mapping studies in sugarcane.

Effectiveness of Homeopathic Medicines as Add-on to Institutional Management Protocol for Acute Encephalitis Syndrome in Children: An Open-Label Randomized Placebo-Controlled Trial

Background Acute encephalitis syndrome (AES) is endemic to certain parts of India, with limited treatment options. In our initial exploratory comparative observational study of 151 patients with AES, there was significantly reduced mortality with adjunctive homeopathy compared to institutional management protocol (IMP). The present randomized placebo-controlled trial brings more statistical rigor to this research program.

Methods This study was conducted at a pediatric unit from 2013 to 2015. Children aged > 6 months and ≤ 18 years and receiving IMP were randomized to receive adjunctive homeopathy (n = 325) or placebo as control (n = 323). The primary effectiveness analysis was based on Glasgow Outcome Scale (GOS). Morbidity was assessed using the Liverpool Outcome Score for Assessing Children at Follow-up. Analysis was by intention to treat.

Results A total of 612 children were analyzed (Homeopathy [H] = 304; Control [C] = 308). The primary outcome, GOS, differed significantly between H and C groups. There was 14.8% death/neuro-vegetative state in the H group compared to 29.8% in the C group. Relative risk was 0.49 (95% confidence interval [CI]: 0.36 to 0.68), with absolute risk reduction of 15.0% (95% CI: 8.6 to 21.6%). Number needed to treat to prevent one additional death/neuro-vegetative state was 6.6 (95% CI: 4.6 to 11.6). Proportional-odds analysis also revealed a greater effect in the H group: odds ratio, 0.40 (95% CI: 0.27 to 0.60). The most frequently used medicines were Belladonna (n = 116), Stramonium (n = 33), Arsenicum album (n = 25), Sulfur (n = 18), Opium (n = 17), and Nux vomica (n = 10).

Conclusion Adjunctive homeopathic medicines may improve clinical outcomes associated with AES. Further randomized and controlled studies, using double-blinded trial design, are recommended to discover if the current findings may be corroborated.

Lolium perenne peptide immunotherapy is well tolerated and elicits a protective B-cell response in seasonal allergic rhinitis patients

BACKGROUND

Systemic allergic reactions are a risk for allergen immunotherapy that utilizes intact allergen preparations. We evaluated the safety, efficacy and immune mechanisms of short-course treatment with adjuvant-free Lolium perenne peptides (LPP) following a 6-week dose-escalation protocol.

METHODS

In a prospective, dose-escalation study, 61 grass pollen-allergic patients received 2 subcutaneous injections of LPP once weekly for 6 weeks. Safety was assessed evaluating local reactions, systemic reactions and adverse events. The clinical effect of LPP was determined by reactivity to the conjunctival provocation test (CPT). Specific IgE, IgG4 and blocking antibodies were measured at baseline (V1), during (V6) and after treatment (V8).

RESULTS

No fatality, serious adverse event or epinephrine use was reported. Mean wheal diameters after injections were <0.6 cm and mean redness diameters <2.5 cm, independent of dose. Transient and mostly mild adverse events were reported in 33 patients. Two patients experienced a grade I and 4 patients a grade II reaction (AWMF classification). At V8, 69.8% of patients became nonreactive to CPT. sIgG4 levels were higher at V6 (8.1-fold, P < .001) and V8 (12.2-fold, P < .001) than at V1. The sIgE:sIgG4 ratio decreased at V6 (-54.6%, P < .001) and V8 (-71.6%, P < .001) compared to V1. The absolute decrease in IgE-facilitated allergen binding was 18% (P < .001) at V6 and 25% (P < .001) at V8.

CONCLUSION

Increasing doses of subcutaneous LPP appeared safe, substantially diminished reactivity to CPT and induced blocking antibodies as early as 4 weeks after treatment initiation. The benefit/risk balance of LPP immunotherapy remains to be further evaluated in large studies.

Proportions of predominant Ergot alkaloids (Claviceps purpurea) detected in Western Canadian grains from 2014 to 2016

Ergot alkaloids, produced by the fungus Claviceps purpurea, are contaminants of cereal crops. Depending on various factors, the relative composition of individual ergot alkaloids can differ among samples. The objective was to determine if the percentage of individual ergot alkaloids were similar across different cereal grains (barley n=39, rye n=7, triticale n=9, wheat n=94) collected in Western Canada over different years. Ergocristine was the predominant alkaloid accounting for half of the total alkaloids in all grain types. This study documented that barley, rye, triticale and wheat collected across Western Canada had similar percentages of ergocornine (6±1%, P=0.201), ergocristine (48±2%, P=0.939), ergocryptine (17±2%, P=0.302) and ergosine (5±0.5%, P=0.239). There were differences between grain types for ergometrine (P=0.027) and ergotamine (P=0.011), which ranged between 6 to 13% and 11 to 24%, respectively, of the total alkaloid content in different cereals. Both barley and wheat alkaloid percentages were similar between 2015 and 2016; ergocornine (7±1%, P=0.969), ergocristine (47±2%, P=0.680), ergocryptine (18±2%, P=0.572), ergometrine (8±1%, P=0.080), ergosine (15±1%, P=0.119) and ergotamine (P=0.189). The ergocornine percentage was higher in wheat (P=0.017) as compared to barley for 2015/2016 samples. Ergometrine was higher in barley (P=0.002) as compared to wheat for 2015/2016 samples. While two of the alkaloid proportions varied statistically, overall proportions of the six ergot alkaloids were comparable among the four grain types collected across Western Canada. If proportions of ergot alkaloids are similar across a region, then it may be deemed acceptable to recommend a maximum total ergot alkaloid concentration for that region. However, areas that exhibit variation among the ergot alkaloid proportions, individual ergot alkaloid guidelines based on a toxic equivalence factor, may be more appropriate. In contrast, since major differences were not seen between years or grain type, from a producer perspective there may be limited biological/toxicological significance for individual alkaloid guidelines.

Transcriptome analysis of granulosa cells after conventional vs long FSH-induced superstimulation in cattle

BACKGROUND

Prolongation of superstimulatory treatment appears to be associated with a greater superovulatory response and with greater oocyte maturation in cattle. A genome-wide bovine oligo-microarray was used to compare the gene expression of granulosa cells collected from ovarian follicles after differing durations of the growing phase induced by exogenous FSH treatment. Cows were given a conventional (4-day) or long (7-day) superstimulatory treatment (25 mg FSH im at 12-h intervals; n = 6 per group), followed by prostaglandin treatment with last FSH and LH treatment 24 h later. Granulosa cells were harvested 24 h after LH treatment.

RESULTS

The expression of 416 genes was down-regulated and 615 genes was up-regulated in the long FSH group compared to the conventional FSH group. Quantification by RT-PCR of 7 genes (NTS, PTGS2, PTX3, RGS2, INHBA, CCND2 and LRP8) supported the microarrays data. Multigene bioinformatic analysis indicates that markers of fertility and follicle maturity were up-regulated in the long FSH group.

CONCLUSION

Using the large gene expression dataset generated by the genomic analysis and our previous associated with the growth phase and gene expression changes post LH, we can conclude that a prolonged FSH-induced growing phase is associated with transcriptomic characteristics of greater follicular maturity and may therefore be more appropriate for optimizing the superovulatory response and developmental competence of oocytes in cattle.

Cardiotoxicity Associated with Nicotinamide Phosphoribosyltransferase Inhibitors in Rodents and in Rat and Human-Derived Cells Lines

Nicotinamide phosphoribosyltransferase (NAMPT) is a pleiotropic protein that functions as an enzyme, cytokine, growth factor and hormone. As a target for oncology, NAMPT is particularly attractive, because it catalyzes the rate-limiting step in the salvage pathway to generate nicotinamide adenine dinucleotide (NAD), a universal energy- and signal-carrying molecule involved in cellular energy metabolism and many homeostatic functions. Inhibition of NAMPT generally results in NAD depletion, followed by ATP reduction and loss of cell viability. Herein, we describe NAMPT inhibitor (NAMPTi)-induced cardiac toxicity in rodents following short-term administration (2-7 days) of NAMPTi's. The cardiac toxicity was interpreted as a functional effect leading to congestive heart failure, characterized by sudden death, thoracic and abdominal effusion, and myocardial degeneration. Based on exposures in the initial in vivo safety rodent studies and cardiotoxicity observed, we conducted studies in rat and human in vitro cardiomyocyte cell systems. Based on those results, combined with human cell line potency data, we demonstrated the toxicity is both on-target and likely human relevant. This toxicity was mitigated in vitro by co-administration of nicotinic acid (NA), which can enable NAD production through the NAMPT-independent pathway; however, this resulted in only partial mitigation in in vivo studies. This work also highlights the usefulness and predictivity of in vitro cardiomyocyte assays using human cells to rank-order compounds against potency in cell-based pharmacology assays. Lastly, this work strengthens the correlation between cardiomyocyte cell viability and functionality, suggesting that these assays together may enable early assessment of cardiotoxicity in vitro prior to conduct of in vivo studies and potentially reduce subsequent attrition due to cardiotoxicity.

A randomized, double-blind, placebo-controlled, dose-finding trial with Lolium perenne peptide immunotherapy

Background

A novel subcutaneous allergen immunotherapy formulation (gpASIT+™) containing Lolium perenne peptides (LPP) and having a short up‐dosing phase has been developed to treat grass pollen–induced seasonal allergic rhinoconjunctivitis. We investigated peptide immunotherapy containing the hydrolysate from perennial ryegrass allergens for the optimum dose in terms of clinical efficacy, immunogenicity and safety.

Methods

This prospective, double‐blind, placebo‐controlled, phase IIb, parallel, four‐arm, dose‐finding study randomized 198 grass pollen–allergic adults to receive placebo or cumulative doses of 70, 170 or 370 μg LPP. All patients received weekly subcutaneous injections, with the active treatment groups reaching assigned doses within 2, 3 and 4 weeks, respectively. Efficacy was assessed by comparing conjunctival provocation test (CPT) reactions at baseline, after 4 weeks and after completion. Grass pollen–specific immunoglobulins were analysed before and after treatment.

Results

Conjunctival provocation test (CPT) response thresholds improved from baseline to V7 by at least one concentration step in 51.2% (170 μg; P = .023), 46.3% (370 μg), and 38.6% (70 μg) of patients receiving LPP vs 25.6% of patients receiving placebo (modified per‐protocol set). Also, 39% of patients in the 170‐μg group became nonreactive to CPT vs 18% in the placebo group. Facilitated allergen‐binding assays revealed a highly significant (P < .001) dose‐dependent reduction in IgE allergen binding across all treatment groups (70 μg: 17.1%; 170 μg: 18.8%; 370 μg: 26.4%). Specific IgG₄ levels increased to 1.6‐fold (70 μg), 3.1‐fold (170 μg) and 3.9‐fold (370 μg) (mPP).

Conclusion

Three‐week immunotherapy with 170 μg LPP reduced CPT reactivity significantly and increased protective specific antibodies.

Comparing the DSM-5 construct of Disruptive Mood Dysregulation Disorder and ICD-10 Mixed Disorder of Emotion and Conduct in the UK Longitudinal Assessment of Manic Symptoms (UK-LAMS) Study

It is important to understand new diagnostic entities in classifications of psychopathology such as the Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) (code F34.8) construct of Disruptive Mood Dysregulation Disorder (DMDD) and to compare it with possible equivalent disorders in other classificatory systems such as the International Classification of Diseases-10 (ICD-10), which has a category that superficially appears similar, that is, Mixed Disorder of Emotion and Conduct (MDEC) (code F92). In this study, the United Kingdom (UK) arm (UK-LAMS) of the US National Institute of Mental Health (NIMH) supported Longitudinal Assessment of Manic Symptoms (LAMS) multi-site study was used to evaluate and retrospectively construct DMDD and MDEC diagnoses in order to compare them and understand the conditions they co-occur with, in order to improve the clinical understanding. In particular, the phenomenology of UK-LAMS participants (n = 117) was used to determine whether DMDD is a unique entity within the DSM-5. The findings showed that 24 of 68 participants with either DMDD or MDEC (35.3%) fulfilled both diagnostic criteria for DMDD and MDEC, suggesting that these entities do contain overlapping features, particularly symptoms relating to Oppositional Defiant Disorder (ODD)/Conduct Disorder (CD), Attention Deficit Hyperactivity Disorder (ADHD)/Hyperkinetic Disorder (HKD) and/or an anxiety disorder. The data also showed that most of the participants who met DMDD criteria also fulfilled the diagnostic criteria for ODD/CD, ADHD, followed by an anxiety disorder. In this context, this raises the issue whether DMDD is a unique construct or whether the symptomology for DMDD can be better explained as a specifier for ODD/CD and ADHD. Unlike DMDD, MDEC clearly specifies that the label should only be used if emotional and conduct disorders co-exist.

Calcium Signaling in the Ventricular Myocardium of the Goto-Kakizaki Type 2 Diabetic Rat

The association between diabetes mellitus (DM) and high mortality linked to cardiovascular disease (CVD) is a major concern worldwide. Clinical and preclinical studies have demonstrated a variety of diastolic and systolic dysfunctions in patients with type 2 diabetes mellitus (T2DM) with the severity of abnormalities depending on the patients' age and duration of diabetes. The cellular basis of hemodynamic dysfunction in a type 2 diabetic heart is still not well understood. The aim of this review is to evaluate our current understanding of contractile dysfunction and disturbances of Ca²⁺ transport in the Goto-Kakizaki (GK) diabetic rat heart. The GK rat is a widely used nonobese, nonhypertensive genetic model of T2DM which is characterized by insulin resistance, elevated blood glucose, alterations in blood lipid profile, and cardiac dysfunction.

105 P75 Neuronal Cells and Fibers in the Bovine Ovary

Neurotrophins are molecules involved in the development and survival of neurons and its cellular projections. Results of recent studies have implicated the local role of the high affinity neurotropin receptor, trkA, in bovine ovarian follicle selection and early luteogenesis (Carrasco et al. 2016 Reprod. Biol. Endocrinol. 14, 47), but innervation and neuropeptide control remains an unexplored aspect of ovarian function. P75 is the low-affinity receptor for all neurotrophins and is expressed in ovarian tissue. The objective of this study was to explore the distribution of P75 neurons and fibres within the ovary and to examine the relationship of these components with follicular development. The ovaries of cows (n = 5) were collected at the time of slaughter, 36 h after induced luteolysis (i.e. proestrus). The ovaries were fixed in 4% paraformaldehyde for 48 h, and samples from the ovarian hilus, medulla, and cortex (3 blocks per ovary) were cryo-sectioned (20–50 µm). Tissue sections were incubated for 48 h with a rabbit antibody against rat P75 or a mouse monoclonal antibody against neurofilament. Immunodetection was visualised by an amplification procedure with horseradish peroxidase using nickel DAB as a chromogen. Sections were counterstained with nuclear fast red for follicle identification. Immunoreactive cell bodies were counted in 10 to 20 fields (40×) per section, and data were expressed based on ovarian areas (cortex, medulla, or hilus) as an average count per 40× field per animal. Data among ovarian regions were compared by ANOVA; differences were considered significant when P < 0.05. Antral follicles ≤5 mm displayed strong immunoreactivity in the theca layer, without reaction in the granulosa cells. In contrast, preovulatory follicles were devoid of P75 immuno-reactivity in the theca layer. Oval P75 immunoreactive neuron-like cells were present in all ovarian areas studied. The neuronal nature of the P75 immunoreactive cells was confirmed by the presence of a similar pattern when adjacent sections were stained for neurofilaments, a protein characteristic of neurons. In the stroma of the ovarian cortex and medulla, neurons were present individually (scattered) rather than grouped; however, a dense network of neurons and fibres was detected immediately beneath the ovarian surface epithelium. No differences between the cortex, medulla, and hilus were found in the mean number of immunoreactive cells (10.6 ± 2.8, 14.4 ± 3.6 and 13.9 ± 2.0 cells/40× field, respectively). Immunoreactive neuron-like cells and fibres were in close proximity to blood vessels in the ovarian medulla. Corpora lutea were devoid of P75 immunoreactivity. In conclusion, results document the existence of a neuronal network in the bovine ovary, displaying an association with follicles at different stages of development. The abundance of neuronal components (i.e. neuron cell bodies and axons) in the ovarian stromal and surface epithelium implies a role of innervation (either extrinsic or intrinsic) in the control of ovarian follicular development and function. Research was supported by the Natural Sciences and Engineering Research Council of Canada.

4 Relationship Between Ovarian Vascularity, Cumulus–Oocyte Morphology and Luteal Development in Four-Month-Old Calves After FSH Stimulation

The objectives of this study were to determine the effect of LH on the blood flow to the ovaries of 4-month-old calves after 2 FSH stimulation protocols, and to examine the relationship between ovarian vascularity after superstimulation to the morphology of the cumulus–oocyte complexes (COC) and luteal function. We hypothesise that ovarian vascularity (detected by 3-dimensional (3D) analysis of Doppler ultrasound cineloops) will increase in response to LH, and the magnitude of change in vascularity would be predictive of (1) a greater proportion of expanded COC, (2) greater development of luteal tissue volume and vascularity at 3 and 7 days after follicle aspiration, and (3) higher levels of plasma progesterone. Ovarian superstimulation was initiated at the beginning of an induced follicular wave in 4-month-old beef calves (n = 16), and beef cattle >16 months of age (control group, adults; n = 8) using either a traditional 4-day or an extended 7-day FSH protocol (n = 8 calves and n = 4 controls per group). Power Doppler ultrasound cineloops were recorded immediately before (i.e. 12 h after the last FSH treatment) and 24 h after LH treatment (before ultrasound-guided follicular aspiration for oocyte collection) to assess ovarian vascularity, and 3 and 7 days after follicular aspiration to assess luteal tissue volume and vascularity. Video segments were analysed in Fiji and Imaris software to obtain the 3D ovarian vascularity index (ratio of blood flow volume to tissue volume). The ovarian vascularity index tended to increase >1.7-fold in response to exogenous LH in both prepubertal calves (pre-LH 1.5 ± 0.4% v. post-LH 2.6 ± 0.7%; P = 0.08) and adult cattle (pre-LH 2.2 ± 0.6% v. post-LH 4.7 ± 0.9%; P = 0.07). Calves with a recovery of >75% of expanded COC had a higher ovarian vascularity index (10.7 ± 2.6% v. 4.8 ± 1.6%; P = 0.06) and luteal vascularity index (15.7 ± 4.5% v. 5.7 ± 2.1%; P < 0.05) 7 days after aspiration than those with <75% expanded COC. Calves in the 7-day FSH protocol had >10-fold higher concentration of plasma progesterone on Day 3 (12.7 ± 7.3 ng mL−1 v. 1.2 ± 0.4 ng mL−1; P < 0.05) and Day 5 (50.6 ± 28.0 ng mL−1 v. 4.5 ± 1.0 ng mL−1; P < 0.05), and ~2-fold higher luteal vascularity index at 7 days after follicle aspiration (13.7 ± 4.6% v. 7.7 ± 2.8%; P < 0.05) than calves in the 4-day FSH protocol, whereas no difference (P > 0.05) was found in control (adult) animals. In conclusion, there was an increase in ovarian vascularity resulting from LH treatment in prepubertal calves and adult cattle. A greater proportion of expansion of COC at 24 h after LH treatment (an indicator of follicular maturation) was related to higher ovarian and luteal vascularity on Day 7 after collection in prepubertal calves, but not in adults. Luteal vascularity on Day 3 was reflective of plasma progesterone concentration, and prepubertal calves in the 7-day FSH protocol had greater plasma progesterone than calves in the 4-day FSH protocol. The use of FSH in calves allows a greater number of follicles for oocyte collection as it does in adult cattle. Research was supported by an NSERC grant.

104 Distribution of Gonadotropin-Releasing Hormone and Kisspeptin Neurons in the Preoptic Area and Hypothalamus During the Estrous Cycle in Cows

Gonadal steroids hormones indirectly regulate gonadotropin-rleasing hormone (GnRH) secretion. Kisspeptin (Kp) co-expresses steroid receptors and modulates GnRH release. The objective of the study was to characterise the number and proportion of GnRH and Kp immunoreactive cells and their association in the preoptic area (POA) and hypothalamus during different phases of the oestrous cycle in cows. Daily ovarian ultrasonography was performed to detect follicle development and ovulation (Day 0) after prostaglandin treatment. On Day 5, cows were assigned randomly to the following groups: proestrus (n = 2), metestrus (n = 2) or diestrus (n = 3). Cows in the diestrus group were killed on Day 8. Cows in the proestrus and metestrus groups were given luteolytic dose of prostaglandin on Day 5.5 and Day 6 and were killed on Day 7 and 24 h after the ensuing ovulation, respectively. Cow heads were perfused with 4% paraformaldehyde via the carotid arteries to fix the brain in situ. The brain-stem (rostral portion of the POA to the mamillary body) was isolated by dissection and placed in 4% paraformaldehyde for 48 h. Following cryoprotection, the tissue block containing the POA and hypothalamus was frozen at –80°C and sectioned serially at a thickness of 50 mm using a cryostat microtome. Every 20th free-floating section was processed for double labelling using 2 sequential immuno-peroxidase reactions and ABC staining; Kp was immuno-labelled with Nickel-DAB at a dilution of 1:10,000 rabbit anti-kisspeptin (AC566, INRA, France), and GnRH was stained with DAB using 1:40,000 rabbit anti-GnRH (LR-5, Dr Benoit). The numbers of neuron cell bodies and fibres were recorded in different areas of the POA and the hypothalamus by brightfield microscopy using 10× and 40× objective lenses. Data were compared among groups by ANOVA. Major aggregations of Kp cells were localised in the mPOA, OVLT, and ARC. Overall, the number of Kp cells was higher in the metestrus v. diestrus group (719 ± 94 v. 378 ± 8; P = 0.01), but was similar to the proestrus group (558 ± 9). The number of Kp cells in the POA (mPOA, OVLT) tended to be higher in the metestrus v. diestrus group (395 ± 56 v. 147 ± 44; P = 0.06), and was intermediate in the proestrus group (206 ± 6). The number of Kp cells in the ARC did not differ among groups (metestrus 310 ± 26, diestrus 206 ± 53, proestrus 321 ± 99; P = 0.4). The number of GnRH cells bodies was not different among groups (metestrus 40 ± 3, diestrus 50 ± 9, proestrus 43 ± 8; combined; P = 0.8), and the distribution was higher in the POA (metestrus 25 ± 2, diestrus 30 ± 3, proestrus 33 ± 2) than hypothalamus. The proportion of GnRH cells in apposition to Kp fibres tended to be highest in the proestrus v. metestrus and diestrus groups (50.5 ± 1% v. 34.1 ± 9% and 31.4 ± 3%; P = 0.09). In conclusion, the number of Kp immunoreactive cells, but not GnRH cells, present in the POA and hypothalamus changed among different phases of the oestrous cycle due primarily to an increase in number of Kp cells in POA during metestrus. The proestrous phase was associated with an increase in apposition between Kp fibres and GnRH cells.